Config.3pm

Langue: en

Version: 2010-10-08 (fedora - 01/12/10)

Section: 3 (Bibliothèques de fonctions)

NAME

Config - access Perl configuration information

SYNOPSIS

     use Config;
     if ($Config{usethreads}) {
         print "has thread support\n"
     } 
 
     use Config qw(myconfig config_sh config_vars config_re);
 
     print myconfig();
 
     print config_sh();
 
     print config_re();
 
     config_vars(qw(osname archname));
 
 

DESCRIPTION

The Config module contains all the information that was available to the "Configure" program at Perl build time (over 900 values).

Shell variables from the config.sh file (written by Configure) are stored in the readonly-variable %Config, indexed by their names.

Values stored in config.sh as 'undef' are returned as undefined values. The perl "exists" function can be used to check if a named variable exists.

For a description of the variables, please have a look at the Glossary file, as written in the Porting folder, or use the url: http://perl5.git.perl.org/perl.git/blob/HEAD:/Porting/Glossary

myconfig()
Returns a textual summary of the major perl configuration values. See also "-V" in ``Switches'' in perlrun.
config_sh()
Returns the entire perl configuration information in the form of the original config.sh shell variable assignment script.
config_re($regex)
Like config_sh() but returns, as a list, only the config entries who's names match the $regex.
config_vars(@names)
Prints to STDOUT the values of the named configuration variable. Each is printed on a separate line in the form:
   name='value';
 
 

Names which are unknown are output as "name='UNKNOWN';". See also "-V:name" in ``Switches'' in perlrun.

EXAMPLE

Here's a more sophisticated example of using %Config:
     use Config;
     use strict;
 
     my %sig_num;
     my @sig_name;
     unless($Config{sig_name} && $Config{sig_num}) {
         die "No sigs?";
     } else {
         my @names = split ' ', $Config{sig_name};
         @sig_num{@names} = split ' ', $Config{sig_num};
         foreach (@names) {
             $sig_name[$sig_num{$_}] ||= $_;
         }   
     }
 
     print "signal #17 = $sig_name[17]\n";
     if ($sig_num{ALRM}) { 
         print "SIGALRM is $sig_num{ALRM}\n";
     }
 
 

WARNING

Because this information is not stored within the perl executable itself it is possible (but unlikely) that the information does not relate to the actual perl binary which is being used to access it.

The Config module is installed into the architecture and version specific library directory ($Config{installarchlib}) and it checks the perl version number when loaded.

The values stored in config.sh may be either single-quoted or double-quoted. Double-quoted strings are handy for those cases where you need to include escape sequences in the strings. To avoid runtime variable interpolation, any "$" and "@" characters are replaced by "\$" and "\@", respectively. This isn't foolproof, of course, so don't embed "\$" or "\@" in double-quoted strings unless you're willing to deal with the consequences. (The slashes will end up escaped and the "$" or "@" will trigger variable interpolation)

GLOSSARY

Most "Config" variables are determined by the "Configure" script on platforms supported by it (which is most UNIX platforms). Some platforms have custom-made "Config" variables, and may thus not have some of the variables described below, or may have extraneous variables specific to that particular port. See the port specific documentation in such cases.

_

_a
From Unix.U:

This variable defines the extension used for ordinary library files. For unix, it is .a. The . is included. Other possible values include .lib.

_exe
From Unix.U:

This variable defines the extension used for executable files. "DJGPP", Cygwin and OS/2 use .exe. Stratus "VOS" uses .pm. On operating systems which do not require a specific extension for executable files, this variable is empty.

_o
From Unix.U:

This variable defines the extension used for object files. For unix, it is .o. The . is included. Other possible values include .obj.

a

afs
From afs.U:

This variable is set to "true" if "AFS" (Andrew File System) is used on the system, "false" otherwise. It is possible to override this with a hint value or command line option, but you'd better know what you are doing.

afsroot
From afs.U:

This variable is by default set to /afs. In the unlikely case this is not the correct root, it is possible to override this with a hint value or command line option. This will be used in subsequent tests for AFSness in the configure and test process.

alignbytes
From alignbytes.U:

This variable holds the number of bytes required to align a double--- or a long double when applicable. Usual values are 2, 4 and 8. The default is eight, for safety.

ansi2knr
From ansi2knr.U:

This variable is set if the user needs to run ansi2knr. Currently, this is not supported, so we just abort.

aphostname
From d_gethname.U:

This variable contains the command which can be used to compute the host name. The command is fully qualified by its absolute path, to make it safe when used by a process with super-user privileges.

api_revision
From patchlevel.U:

The three variables, api_revision, api_version, and api_subversion, specify the version of the oldest perl binary compatible with the present perl. In a full version string such as 5.6.1, api_revision is the 5. Prior to 5.5.640, the format was a floating point number, like 5.00563.

perl.c:incpush() and lib/lib.pm will automatically search in $sitelib/.. for older directories back to the limit specified by these api_ variables. This is only useful if you have a perl library directory tree structured like the default one. See "INSTALL" for how this works. The versioned site_perl directory was introduced in 5.005, so that is the lowest possible value. The version list appropriate for the current system is determined in inc_version_list.U.

"XXX" To do: Since compatibility can depend on compile time options (such as bincompat, longlong, etc.) it should (perhaps) be set by Configure, but currently it isn't. Currently, we read a hard-wired value from patchlevel.h. Perhaps what we ought to do is take the hard-wired value from patchlevel.h but then modify it if the current Configure options warrant. patchlevel.h then would use an #ifdef guard.

api_subversion
From patchlevel.U:

The three variables, api_revision, api_version, and api_subversion, specify the version of the oldest perl binary compatible with the present perl. In a full version string such as 5.6.1, api_subversion is the 1. See api_revision for full details.

api_version
From patchlevel.U:

The three variables, api_revision, api_version, and api_subversion, specify the version of the oldest perl binary compatible with the present perl. In a full version string such as 5.6.1, api_version is the 6. See api_revision for full details. As a special case, 5.5.0 is rendered in the old-style as 5.005. (In the 5.005_0x maintenance series, this was the only versioned directory in $sitelib.)

api_versionstring
From patchlevel.U:

This variable combines api_revision, api_version, and api_subversion in a format such as 5.6.1 (or 5_6_1) suitable for use as a directory name. This is filesystem dependent.

ar
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the ar program. After Configure runs, the value is reset to a plain "ar" and is not useful.

archlib
From archlib.U:

This variable holds the name of the directory in which the user wants to put architecture-dependent public library files for $package. It is most often a local directory such as /usr/local/lib. Programs using this variable must be prepared to deal with filename expansion.

archlibexp
From archlib.U:

This variable is the same as the archlib variable, but is filename expanded at configuration time, for convenient use.

archname
From archname.U:

This variable is a short name to characterize the current architecture. It is used mainly to construct the default archlib.

archname64
From use64bits.U:

This variable is used for the 64-bitness part of $archname.

archobjs
From Unix.U:

This variable defines any additional objects that must be linked in with the program on this architecture. On unix, it is usually empty. It is typically used to include emulations of unix calls or other facilities. For perl on OS/2, for example, this would include os2/os2.obj.

asctime_r_proto
From d_asctime_r.U:

This variable encodes the prototype of asctime_r. It is zero if d_asctime_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_asctime_r is defined.

awk
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the awk program. After Configure runs, the value is reset to a plain "awk" and is not useful.

b

baserev
From baserev.U:

The base revision level of this package, from the .package file.

bash
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

bin
From bin.U:

This variable holds the name of the directory in which the user wants to put publicly executable images for the package in question. It is most often a local directory such as /usr/local/bin. Programs using this variable must be prepared to deal with ~name substitution.

bin_ELF
From dlsrc.U:

This variable saves the result from configure if generated binaries are in "ELF" format. Only set to defined when the test has actually been performed, and the result was positive.

binexp
From bin.U:

This is the same as the bin variable, but is filename expanded at configuration time, for use in your makefiles.

bison
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the bison program. After Configure runs, the value is reset to a plain "bison" and is not useful.

byacc
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the byacc program. After Configure runs, the value is reset to a plain "byacc" and is not useful.

byteorder
From byteorder.U:

This variable holds the byte order in a "UV". In the following, larger digits indicate more significance. The variable byteorder is either 4321 on a big-endian machine, or 1234 on a little-endian, or 87654321 on a Cray ... or 3412 with weird order !

c

c
From n.U:

This variable contains the \c string if that is what causes the echo command to suppress newline. Otherwise it is null. Correct usage is $echo $n ``prompt for a question: $c''.

castflags
From d_castneg.U:

This variable contains a flag that precise difficulties the compiler has casting odd floating values to unsigned long: 0 = ok 1 = couldn't cast < 0 2 = couldn't cast >= 0x80000000 4 = couldn't cast in argument expression list

cat
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the cat program. After Configure runs, the value is reset to a plain "cat" and is not useful.

cc
From cc.U:

This variable holds the name of a command to execute a C compiler which can resolve multiple global references that happen to have the same name. Usual values are "cc" and "gcc". Fervent "ANSI" compilers may be called "c89". "AIX" has xlc.

cccdlflags
From dlsrc.U:

This variable contains any special flags that might need to be passed with "cc -c" to compile modules to be used to create a shared library that will be used for dynamic loading. For hpux, this should be +z. It is up to the makefile to use it.

ccdlflags
From dlsrc.U:

This variable contains any special flags that might need to be passed to cc to link with a shared library for dynamic loading. It is up to the makefile to use it. For sunos 4.1, it should be empty.

ccflags
From ccflags.U:

This variable contains any additional C compiler flags desired by the user. It is up to the Makefile to use this.

ccflags_uselargefiles
From uselfs.U:

This variable contains the compiler flags needed by large file builds and added to ccflags by hints files.

ccname
From Checkcc.U:

This can set either by hints files or by Configure. If using gcc, this is gcc, and if not, usually equal to cc, unimpressive, no? Some platforms, however, make good use of this by storing the flavor of the C compiler being used here. For example if using the Sun WorkShop suite, ccname will be "workshop".

ccsymbols
From Cppsym.U:

The variable contains the symbols defined by the C compiler alone. The symbols defined by cpp or by cc when it calls cpp are not in this list, see cppsymbols and cppccsymbols. The list is a space-separated list of symbol=value tokens.

ccversion
From Checkcc.U:

This can set either by hints files or by Configure. If using a (non-gcc) vendor cc, this variable may contain a version for the compiler.

cf_by
From cf_who.U:

Login name of the person who ran the Configure script and answered the questions. This is used to tag both config.sh and config_h.SH.

cf_email
From cf_email.U:

Electronic mail address of the person who ran Configure. This can be used by units that require the user's e-mail, like MailList.U.

cf_time
From cf_who.U:

Holds the output of the "date" command when the configuration file was produced. This is used to tag both config.sh and config_h.SH.

charbits
From charsize.U:

This variable contains the value of the "CHARBITS" symbol, which indicates to the C program how many bits there are in a character.

charsize
From charsize.U:

This variable contains the value of the "CHARSIZE" symbol, which indicates to the C program how many bytes there are in a character.

chgrp
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

chmod
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the chmod program. After Configure runs, the value is reset to a plain "chmod" and is not useful.

chown
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

clocktype
From d_times.U:

This variable holds the type returned by times(). It can be long, or clock_t on "BSD" sites (in which case <sys/types.h> should be included).

comm
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the comm program. After Configure runs, the value is reset to a plain "comm" and is not useful.

compress
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

config_arg0
From Options.U:

This variable contains the string used to invoke the Configure command, as reported by the shell in the $0 variable.

config_argc
From Options.U:

This variable countains the number of command-line arguments passed to Configure, as reported by the shell in the $# variable. The individual arguments are stored as variables config_argc1, config_argc2, etc.

config_args
From Options.U:

This variable contains a single string giving the command-line arguments passed to Configure.  Spaces within arguments,
quotes, and escaped characters are not correctly preserved. To reconstruct the command line, you must assemble the individual command line pieces, given in config_arg[0-9]*.

contains
From contains.U:

This variable holds the command to do a grep with a proper return status. On most sane systems it is simply "grep". On insane systems it is a grep followed by a cat followed by a test. This variable is primarily for the use of other Configure units.

cp
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the cp program. After Configure runs, the value is reset to a plain "cp" and is not useful.

cpio
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

cpp
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the cpp program. After Configure runs, the value is reset to a plain "cpp" and is not useful.

cpp_stuff
From cpp_stuff.U:

This variable contains an identification of the concatenation mechanism used by the C preprocessor.

cppccsymbols
From Cppsym.U:

The variable contains the symbols defined by the C compiler when it calls cpp. The symbols defined by the cc alone or cpp alone are not in this list, see ccsymbols and cppsymbols. The list is a space-separated list of symbol=value tokens.

cppflags
From ccflags.U:

This variable holds the flags that will be passed to the C pre- processor. It is up to the Makefile to use it.

cpplast
From cppstdin.U:

This variable has the same functionality as cppminus, only it applies to cpprun and not cppstdin.

cppminus
From cppstdin.U:

This variable contains the second part of the string which will invoke the C preprocessor on the standard input and produce to standard output. This variable will have the value "-" if cppstdin needs a minus to specify standard input, otherwise the value is "".

cpprun
From cppstdin.U:

This variable contains the command which will invoke a C preprocessor on standard input and put the output to stdout. It is guaranteed not to be a wrapper and may be a null string if no preprocessor can be made directly available. This preprocessor might be different from the one used by the C compiler. Don't forget to append cpplast after the preprocessor options.

cppstdin
From cppstdin.U:

This variable contains the command which will invoke the C preprocessor on standard input and put the output to stdout. It is primarily used by other Configure units that ask about preprocessor symbols.

cppsymbols
From Cppsym.U:

The variable contains the symbols defined by the C preprocessor alone. The symbols defined by cc or by cc when it calls cpp are not in this list, see ccsymbols and cppccsymbols. The list is a space-separated list of symbol=value tokens.

crypt_r_proto
From d_crypt_r.U:

This variable encodes the prototype of crypt_r. It is zero if d_crypt_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_crypt_r is defined.

cryptlib
From d_crypt.U:

This variable holds -lcrypt or the path to a libcrypt.a archive if the crypt() function is not defined in the standard C library. It is up to the Makefile to use this.

csh
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the csh program. After Configure runs, the value is reset to a plain "csh" and is not useful.

ctermid_r_proto
From d_ctermid_r.U:

This variable encodes the prototype of ctermid_r. It is zero if d_ctermid_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_ctermid_r is defined.

ctime_r_proto
From d_ctime_r.U:

This variable encodes the prototype of ctime_r. It is zero if d_ctime_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_ctime_r is defined.

d

d__fwalk
From d__fwalk.U:

This variable conditionally defines "HAS__FWALK" if _fwalk() is available to apply a function to all the file handles.

d_access
From d_access.U:

This variable conditionally defines "HAS_ACCESS" if the access() system call is available to check for access permissions using real IDs.

d_accessx
From d_accessx.U:

This variable conditionally defines the "HAS_ACCESSX" symbol, which indicates to the C program that the accessx() routine is available.

d_aintl
From d_aintl.U:

This variable conditionally defines the "HAS_AINTL" symbol, which indicates to the C program that the aintl() routine is available. If copysignl is also present we can emulate modfl.

d_alarm
From d_alarm.U:

This variable conditionally defines the "HAS_ALARM" symbol, which indicates to the C program that the alarm() routine is available.

d_archlib
From archlib.U:

This variable conditionally defines "ARCHLIB" to hold the pathname of architecture-dependent library files for $package. If $archlib is the same as $privlib, then this is set to undef.

d_asctime64
From d_timefuncs64.U:

This variable conditionally defines the HAS_ASCTIME64 symbol, which indicates to the C program that the asctime64 () routine is available.

d_asctime_r
From d_asctime_r.U:

This variable conditionally defines the "HAS_ASCTIME_R" symbol, which indicates to the C program that the asctime_r() routine is available.

d_atolf
From atolf.U:

This variable conditionally defines the "HAS_ATOLF" symbol, which indicates to the C program that the atolf() routine is available.

d_atoll
From atoll.U:

This variable conditionally defines the "HAS_ATOLL" symbol, which indicates to the C program that the atoll() routine is available.

d_attribute_deprecated
From d_attribut.U:

This variable conditionally defines "HASATTRIBUTE_DEPRECATED", which indicates that "GCC" can handle the attribute for marking deprecated APIs

d_attribute_format
From d_attribut.U:

This variable conditionally defines "HASATTRIBUTE_FORMAT", which indicates the C compiler can check for printf-like formats.

d_attribute_malloc
From d_attribut.U:

This variable conditionally defines "HASATTRIBUTE_MALLOC", which indicates the C compiler can understand functions as having malloc-like semantics.

d_attribute_nonnull
From d_attribut.U:

This variable conditionally defines "HASATTRIBUTE_NONNULL", which indicates that the C compiler can know that certain arguments must not be "NULL", and will check accordingly at compile time.

d_attribute_noreturn
From d_attribut.U:

This variable conditionally defines "HASATTRIBUTE_NORETURN", which indicates that the C compiler can know that certain functions are guaranteed never to return.

d_attribute_pure
From d_attribut.U:

This variable conditionally defines "HASATTRIBUTE_PURE", which indicates that the C compiler can know that certain functions are "pure" functions, meaning that they have no side effects, and only rely on function input and/or global data for their results.

d_attribute_unused
From d_attribut.U:

This variable conditionally defines "HASATTRIBUTE_UNUSED", which indicates that the C compiler can know that certain variables and arguments may not always be used, and to not throw warnings if they don't get used.

d_attribute_warn_unused_result
From d_attribut.U:

This variable conditionally defines "HASATTRIBUTE_WARN_UNUSED_RESULT", which indicates that the C compiler can know that certain functions have a return values that must not be ignored, such as malloc() or open().

d_bcmp
From d_bcmp.U:

This variable conditionally defines the "HAS_BCMP" symbol if the bcmp() routine is available to compare strings.

d_bcopy
From d_bcopy.U:

This variable conditionally defines the "HAS_BCOPY" symbol if the bcopy() routine is available to copy strings.

d_bsd
From Guess.U:

This symbol conditionally defines the symbol "BSD" when running on a "BSD" system.

d_bsdgetpgrp
From d_getpgrp.U:

This variable conditionally defines "USE_BSD_GETPGRP" if getpgrp needs one arguments whereas "USG" one needs none.

d_bsdsetpgrp
From d_setpgrp.U:

This variable conditionally defines "USE_BSD_SETPGRP" if setpgrp needs two arguments whereas "USG" one needs none. See also d_setpgid for a "POSIX" interface.

d_builtin_choose_expr
From d_builtin.U:

This conditionally defines "HAS_BUILTIN_CHOOSE_EXPR", which indicates that the compiler supports __builtin_choose_expr(x,y,z). This built-in function is analogous to the "x?y:z" operator in C, except that the expression returned has its type unaltered by promotion rules. Also, the built-in function does not evaluate the expression that was not chosen.

d_builtin_expect
From d_builtin.U:

This conditionally defines "HAS_BUILTIN_EXPECT", which indicates that the compiler supports __builtin_expect(exp,c). You may use __builtin_expect to provide the compiler with branch prediction information.

d_bzero
From d_bzero.U:

This variable conditionally defines the "HAS_BZERO" symbol if the bzero() routine is available to set memory to 0.

d_c99_variadic_macros
From d_c99_variadic.U:

This variable conditionally defines the HAS_C99_VARIADIC_MACROS symbol, which indicates to the C program that C99 variadic macros are available.

d_casti32
From d_casti32.U:

This variable conditionally defines CASTI32, which indicates whether the C compiler can cast large floats to 32-bit ints.

d_castneg
From d_castneg.U:

This variable conditionally defines "CASTNEG", which indicates wether the C compiler can cast negative float to unsigned.

d_charvspr
From d_vprintf.U:

This variable conditionally defines "CHARVSPRINTF" if this system has vsprintf returning type (char*). The trend seems to be to declare it as ``int vsprintf()''.

d_chown
From d_chown.U:

This variable conditionally defines the "HAS_CHOWN" symbol, which indicates to the C program that the chown() routine is available.

d_chroot
From d_chroot.U:

This variable conditionally defines the "HAS_CHROOT" symbol, which indicates to the C program that the chroot() routine is available.

d_chsize
From d_chsize.U:

This variable conditionally defines the "CHSIZE" symbol, which indicates to the C program that the chsize() routine is available to truncate files. You might need a -lx to get this routine.

d_class
From d_class.U:

This variable conditionally defines the "HAS_CLASS" symbol, which indicates to the C program that the class() routine is available.

d_clearenv
From d_clearenv.U:

This variable conditionally defines the "HAS_CLEARENV" symbol, which indicates to the C program that the clearenv () routine is available.

d_closedir
From d_closedir.U:

This variable conditionally defines "HAS_CLOSEDIR" if closedir() is available.

d_cmsghdr_s
From d_cmsghdr_s.U:

This variable conditionally defines the "HAS_STRUCT_CMSGHDR" symbol, which indicates that the struct cmsghdr is supported.

d_const
From d_const.U:

This variable conditionally defines the "HASCONST" symbol, which indicates to the C program that this C compiler knows about the const type.

d_copysignl
From d_copysignl.U:

This variable conditionally defines the "HAS_COPYSIGNL" symbol, which indicates to the C program that the copysignl() routine is available. If aintl is also present we can emulate modfl.

d_cplusplus
From d_cplusplus.U:

This variable conditionally defines the "USE_CPLUSPLUS" symbol, which indicates that a C++ compiler was used to compiled Perl and will be used to compile extensions.

d_crypt
From d_crypt.U:

This variable conditionally defines the "CRYPT" symbol, which indicates to the C program that the crypt() routine is available to encrypt passwords and the like.

d_crypt_r
From d_crypt_r.U:

This variable conditionally defines the "HAS_CRYPT_R" symbol, which indicates to the C program that the crypt_r() routine is available.

d_csh
From d_csh.U:

This variable conditionally defines the "CSH" symbol, which indicates to the C program that the C-shell exists.

d_ctermid
From d_ctermid.U:

This variable conditionally defines "CTERMID" if ctermid() is available to generate filename for terminal.

d_ctermid_r
From d_ctermid_r.U:

This variable conditionally defines the "HAS_CTERMID_R" symbol, which indicates to the C program that the ctermid_r() routine is available.

d_ctime64
From d_timefuncs64.U:

This variable conditionally defines the HAS_CTIME64 symbol, which indicates to the C program that the ctime64 () routine is available.

d_ctime_r
From d_ctime_r.U:

This variable conditionally defines the "HAS_CTIME_R" symbol, which indicates to the C program that the ctime_r() routine is available.

d_cuserid
From d_cuserid.U:

This variable conditionally defines the "HAS_CUSERID" symbol, which indicates to the C program that the cuserid() routine is available to get character login names.

d_dbl_dig
From d_dbl_dig.U:

This variable conditionally defines d_dbl_dig if this system's header files provide "DBL_DIG", which is the number of significant digits in a double precision number.

d_dbminitproto
From d_dbminitproto.U:

This variable conditionally defines the "HAS_DBMINIT_PROTO" symbol, which indicates to the C program that the system provides a prototype for the dbminit() function. Otherwise, it is up to the program to supply one.

d_difftime
From d_difftime.U:

This variable conditionally defines the "HAS_DIFFTIME" symbol, which indicates to the C program that the difftime() routine is available.

d_difftime64
From d_timefuncs64.U:

This variable conditionally defines the HAS_DIFFTIME64 symbol, which indicates to the C program that the difftime64 () routine is available.

d_dir_dd_fd
From d_dir_dd_fd.U:

This variable conditionally defines the "HAS_DIR_DD_FD" symbol, which indicates that the "DIR" directory stream type contains a member variable called dd_fd.

d_dirfd
From d_dirfd.U:

This variable conditionally defines the "HAS_DIRFD" constant, which indicates to the C program that dirfd() is available to return the file descriptor of a directory stream.

d_dirnamlen
From i_dirent.U:

This variable conditionally defines "DIRNAMLEN", which indicates to the C program that the length of directory entry names is provided by a d_namelen field.

d_dlerror
From d_dlerror.U:

This variable conditionally defines the "HAS_DLERROR" symbol, which indicates to the C program that the dlerror() routine is available.

d_dlopen
From d_dlopen.U:

This variable conditionally defines the "HAS_DLOPEN" symbol, which indicates to the C program that the dlopen() routine is available.

d_dlsymun
From d_dlsymun.U:

This variable conditionally defines "DLSYM_NEEDS_UNDERSCORE", which indicates that we need to prepend an underscore to the symbol name before calling dlsym().

d_dosuid
From d_dosuid.U:

This variable conditionally defines the symbol "DOSUID", which tells the C program that it should insert setuid emulation code on hosts which have setuid #! scripts disabled.

d_drand48_r
From d_drand48_r.U:

This variable conditionally defines the HAS_DRAND48_R symbol, which indicates to the C program that the drand48_r() routine is available.

d_drand48proto
From d_drand48proto.U:

This variable conditionally defines the HAS_DRAND48_PROTO symbol, which indicates to the C program that the system provides a prototype for the drand48() function. Otherwise, it is up to the program to supply one.

d_dup2
From d_dup2.U:

This variable conditionally defines HAS_DUP2 if dup2() is available to duplicate file descriptors.

d_eaccess
From d_eaccess.U:

This variable conditionally defines the "HAS_EACCESS" symbol, which indicates to the C program that the eaccess() routine is available.

d_endgrent
From d_endgrent.U:

This variable conditionally defines the "HAS_ENDGRENT" symbol, which indicates to the C program that the endgrent() routine is available for sequential access of the group database.

d_endgrent_r
From d_endgrent_r.U:

This variable conditionally defines the "HAS_ENDGRENT_R" symbol, which indicates to the C program that the endgrent_r() routine is available.

d_endhent
From d_endhent.U:

This variable conditionally defines "HAS_ENDHOSTENT" if endhostent() is available to close whatever was being used for host queries.

d_endhostent_r
From d_endhostent_r.U:

This variable conditionally defines the "HAS_ENDHOSTENT_R" symbol, which indicates to the C program that the endhostent_r() routine is available.

d_endnent
From d_endnent.U:

This variable conditionally defines "HAS_ENDNETENT" if endnetent() is available to close whatever was being used for network queries.

d_endnetent_r
From d_endnetent_r.U:

This variable conditionally defines the "HAS_ENDNETENT_R" symbol, which indicates to the C program that the endnetent_r() routine is available.

d_endpent
From d_endpent.U:

This variable conditionally defines "HAS_ENDPROTOENT" if endprotoent() is available to close whatever was being used for protocol queries.

d_endprotoent_r
From d_endprotoent_r.U:

This variable conditionally defines the "HAS_ENDPROTOENT_R" symbol, which indicates to the C program that the endprotoent_r() routine is available.

d_endpwent
From d_endpwent.U:

This variable conditionally defines the "HAS_ENDPWENT" symbol, which indicates to the C program that the endpwent() routine is available for sequential access of the passwd database.

d_endpwent_r
From d_endpwent_r.U:

This variable conditionally defines the "HAS_ENDPWENT_R" symbol, which indicates to the C program that the endpwent_r() routine is available.

d_endsent
From d_endsent.U:

This variable conditionally defines "HAS_ENDSERVENT" if endservent() is available to close whatever was being used for service queries.

d_endservent_r
From d_endservent_r.U:

This variable conditionally defines the "HAS_ENDSERVENT_R" symbol, which indicates to the C program that the endservent_r() routine is available.

d_eofnblk
From nblock_io.U:

This variable conditionally defines "EOF_NONBLOCK" if "EOF" can be seen when reading from a non-blocking I/O source.

d_eunice
From Guess.U:

This variable conditionally defines the symbols "EUNICE" and "VAX", which alerts the C program that it must deal with ideosyncracies of "VMS".

d_faststdio
From d_faststdio.U:

This variable conditionally defines the "HAS_FAST_STDIO" symbol, which indicates to the C program that the ``fast stdio'' is available to manipulate the stdio buffers directly.

d_fchdir
From d_fchdir.U:

This variable conditionally defines the "HAS_FCHDIR" symbol, which indicates to the C program that the fchdir() routine is available.

d_fchmod
From d_fchmod.U:

This variable conditionally defines the "HAS_FCHMOD" symbol, which indicates to the C program that the fchmod() routine is available to change mode of opened files.

d_fchown
From d_fchown.U:

This variable conditionally defines the "HAS_FCHOWN" symbol, which indicates to the C program that the fchown() routine is available to change ownership of opened files.

d_fcntl
From d_fcntl.U:

This variable conditionally defines the "HAS_FCNTL" symbol, and indicates whether the fcntl() function exists

d_fcntl_can_lock
From d_fcntl_can_lock.U:

This variable conditionally defines the "FCNTL_CAN_LOCK" symbol and indicates whether file locking with fcntl() works.

d_fd_macros
From d_fd_set.U:

This variable contains the eventual value of the "HAS_FD_MACROS" symbol, which indicates if your C compiler knows about the macros which manipulate an fd_set.

d_fd_set
From d_fd_set.U:

This variable contains the eventual value of the "HAS_FD_SET" symbol, which indicates if your C compiler knows about the fd_set typedef.

d_fds_bits
From d_fd_set.U:

This variable contains the eventual value of the "HAS_FDS_BITS" symbol, which indicates if your fd_set typedef contains the fds_bits member. If you have an fd_set typedef, but the dweebs who installed it did a half-fast job and neglected to provide the macros to manipulate an fd_set, "HAS_FDS_BITS" will let us know how to fix the gaffe.

d_fgetpos
From d_fgetpos.U:

This variable conditionally defines "HAS_FGETPOS" if fgetpos() is available to get the file position indicator.

d_finite
From d_finite.U:

This variable conditionally defines the "HAS_FINITE" symbol, which indicates to the C program that the finite() routine is available.

d_finitel
From d_finitel.U:

This variable conditionally defines the "HAS_FINITEL" symbol, which indicates to the C program that the finitel() routine is available.

d_flexfnam
From d_flexfnam.U:

This variable conditionally defines the "FLEXFILENAMES" symbol, which indicates that the system supports filenames longer than 14 characters.

d_flock
From d_flock.U:

This variable conditionally defines "HAS_FLOCK" if flock() is available to do file locking.

d_flockproto
From d_flockproto.U:

This variable conditionally defines the "HAS_FLOCK_PROTO" symbol, which indicates to the C program that the system provides a prototype for the flock() function. Otherwise, it is up to the program to supply one.

d_fork
From d_fork.U:

This variable conditionally defines the "HAS_FORK" symbol, which indicates to the C program that the fork() routine is available.

d_fp_class
From d_fp_class.U:

This variable conditionally defines the "HAS_FP_CLASS" symbol, which indicates to the C program that the fp_class() routine is available.

d_fpathconf
From d_pathconf.U:

This variable conditionally defines the "HAS_FPATHCONF" symbol, which indicates to the C program that the pathconf() routine is available to determine file-system related limits and options associated with a given open file descriptor.

d_fpclass
From d_fpclass.U:

This variable conditionally defines the "HAS_FPCLASS" symbol, which indicates to the C program that the fpclass() routine is available.

d_fpclassify
From d_fpclassify.U:

This variable conditionally defines the "HAS_FPCLASSIFY" symbol, which indicates to the C program that the fpclassify() routine is available.

d_fpclassl
From d_fpclassl.U:

This variable conditionally defines the "HAS_FPCLASSL" symbol, which indicates to the C program that the fpclassl() routine is available.

d_fpos64_t
From d_fpos64_t.U:

This symbol will be defined if the C compiler supports fpos64_t.

d_frexpl
From d_frexpl.U:

This variable conditionally defines the "HAS_FREXPL" symbol, which indicates to the C program that the frexpl() routine is available.

d_fs_data_s
From d_fs_data_s.U:

This variable conditionally defines the "HAS_STRUCT_FS_DATA" symbol, which indicates that the struct fs_data is supported.

d_fseeko
From d_fseeko.U:

This variable conditionally defines the "HAS_FSEEKO" symbol, which indicates to the C program that the fseeko() routine is available.

d_fsetpos
From d_fsetpos.U:

This variable conditionally defines "HAS_FSETPOS" if fsetpos() is available to set the file position indicator.

d_fstatfs
From d_fstatfs.U:

This variable conditionally defines the "HAS_FSTATFS" symbol, which indicates to the C program that the fstatfs() routine is available.

d_fstatvfs
From d_statvfs.U:

This variable conditionally defines the "HAS_FSTATVFS" symbol, which indicates to the C program that the fstatvfs() routine is available.

d_fsync
From d_fsync.U:

This variable conditionally defines the "HAS_FSYNC" symbol, which indicates to the C program that the fsync() routine is available.

d_ftello
From d_ftello.U:

This variable conditionally defines the "HAS_FTELLO" symbol, which indicates to the C program that the ftello() routine is available.

d_ftime
From d_ftime.U:

This variable conditionally defines the "HAS_FTIME" symbol, which indicates that the ftime() routine exists. The ftime() routine is basically a sub-second accuracy clock.

d_futimes
From d_futimes.U:

This variable conditionally defines the "HAS_FUTIMES" symbol, which indicates to the C program that the futimes() routine is available.

d_Gconvert
From d_gconvert.U:

This variable holds what Gconvert is defined as to convert floating point numbers into strings. By default, Configure sets "this" macro to use the first of gconvert, gcvt, or sprintf that pass sprintf-%g-like behaviour tests. If perl is using long doubles, the macro uses the first of the following functions that pass Configure's tests: qgcvt, sprintf (if Configure knows how to make sprintf format long doubles---see sPRIgldbl), gconvert, gcvt, and sprintf (casting to double). The gconvert_preference and gconvert_ld_preference variables can be used to alter Configure's preferences, for doubles and long doubles, respectively. If present, they contain a space-separated list of one or more of the above function names in the order they should be tried.

d_Gconvert may be set to override Configure with a platform- specific function. If this function expects a double, a different value may need to be set by the uselongdouble.cbu call-back unit so that long doubles can be formatted without loss of precision.

d_gdbm_ndbm_h_uses_prototypes
From i_ndbm.U:

This variable conditionally defines the "NDBM_H_USES_PROTOTYPES" symbol, which indicates that the gdbm-ndbm.h include file uses real "ANSI" C prototypes instead of K&R style function declarations. K&R style declarations are unsupported in C++, so the include file requires special handling when using a C++ compiler and this variable is undefined. Consult the different d_*ndbm_h_uses_prototypes variables to get the same information for alternative ndbm.h include files.

d_gdbmndbm_h_uses_prototypes
From i_ndbm.U:

This variable conditionally defines the "NDBM_H_USES_PROTOTYPES" symbol, which indicates that the gdbm/ndbm.h include file uses real "ANSI" C prototypes instead of K&R style function declarations. K&R style declarations are unsupported in C++, so the include file requires special handling when using a C++ compiler and this variable is undefined. Consult the different d_*ndbm_h_uses_prototypes variables to get the same information for alternative ndbm.h include files.

d_getaddrinfo
From d_getaddrinfo.U:

This variable conditionally defines the "HAS_GETADDRINFO" symbol, which indicates to the C program that the getaddrinfo() function is available.

d_getcwd
From d_getcwd.U:

This variable conditionally defines the "HAS_GETCWD" symbol, which indicates to the C program that the getcwd() routine is available to get the current working directory.

d_getespwnam
From d_getespwnam.U:

This variable conditionally defines "HAS_GETESPWNAM" if getespwnam() is available to retrieve enchanced (shadow) password entries by name.

d_getfsstat
From d_getfsstat.U:

This variable conditionally defines the "HAS_GETFSSTAT" symbol, which indicates to the C program that the getfsstat() routine is available.

d_getgrent
From d_getgrent.U:

This variable conditionally defines the "HAS_GETGRENT" symbol, which indicates to the C program that the getgrent() routine is available for sequential access of the group database.

d_getgrent_r
From d_getgrent_r.U:

This variable conditionally defines the "HAS_GETGRENT_R" symbol, which indicates to the C program that the getgrent_r() routine is available.

d_getgrgid_r
From d_getgrgid_r.U:

This variable conditionally defines the "HAS_GETGRGID_R" symbol, which indicates to the C program that the getgrgid_r() routine is available.

d_getgrnam_r
From d_getgrnam_r.U:

This variable conditionally defines the "HAS_GETGRNAM_R" symbol, which indicates to the C program that the getgrnam_r() routine is available.

d_getgrps
From d_getgrps.U:

This variable conditionally defines the "HAS_GETGROUPS" symbol, which indicates to the C program that the getgroups() routine is available to get the list of process groups.

d_gethbyaddr
From d_gethbyad.U:

This variable conditionally defines the "HAS_GETHOSTBYADDR" symbol, which indicates to the C program that the gethostbyaddr() routine is available to look up hosts by their "IP" addresses.

d_gethbyname
From d_gethbynm.U:

This variable conditionally defines the "HAS_GETHOSTBYNAME" symbol, which indicates to the C program that the gethostbyname() routine is available to look up host names in some data base or other.

d_gethent
From d_gethent.U:

This variable conditionally defines "HAS_GETHOSTENT" if gethostent() is available to look up host names in some data base or another.

d_gethname
From d_gethname.U:

This variable conditionally defines the "HAS_GETHOSTNAME" symbol, which indicates to the C program that the gethostname() routine may be used to derive the host name.

d_gethostbyaddr_r
From d_gethostbyaddr_r.U:

This variable conditionally defines the "HAS_GETHOSTBYADDR_R" symbol, which indicates to the C program that the gethostbyaddr_r() routine is available.

d_gethostbyname_r
From d_gethostbyname_r.U:

This variable conditionally defines the "HAS_GETHOSTBYNAME_R" symbol, which indicates to the C program that the gethostbyname_r() routine is available.

d_gethostent_r
From d_gethostent_r.U:

This variable conditionally defines the "HAS_GETHOSTENT_R" symbol, which indicates to the C program that the gethostent_r() routine is available.

d_gethostprotos
From d_gethostprotos.U:

This variable conditionally defines the "HAS_GETHOST_PROTOS" symbol, which indicates to the C program that <netdb.h> supplies prototypes for the various gethost*() functions. See also netdbtype.U for probing for various netdb types.

d_getitimer
From d_getitimer.U:

This variable conditionally defines the "HAS_GETITIMER" symbol, which indicates to the C program that the getitimer() routine is available.

d_getlogin
From d_getlogin.U:

This variable conditionally defines the "HAS_GETLOGIN" symbol, which indicates to the C program that the getlogin() routine is available to get the login name.

d_getlogin_r
From d_getlogin_r.U:

This variable conditionally defines the "HAS_GETLOGIN_R" symbol, which indicates to the C program that the getlogin_r() routine is available.

d_getmnt
From d_getmnt.U:

This variable conditionally defines the "HAS_GETMNT" symbol, which indicates to the C program that the getmnt() routine is available to retrieve one or more mount info blocks by filename.

d_getmntent
From d_getmntent.U:

This variable conditionally defines the "HAS_GETMNTENT" symbol, which indicates to the C program that the getmntent() routine is available to iterate through mounted files to get their mount info.

d_getnameinfo
From d_getnameinfo.U:

This variable conditionally defines the "HAS_GETNAMEINFO" symbol, which indicates to the C program that the getnameinfo() function is available.

d_getnbyaddr
From d_getnbyad.U:

This variable conditionally defines the "HAS_GETNETBYADDR" symbol, which indicates to the C program that the getnetbyaddr() routine is available to look up networks by their "IP" addresses.

d_getnbyname
From d_getnbynm.U:

This variable conditionally defines the "HAS_GETNETBYNAME" symbol, which indicates to the C program that the getnetbyname() routine is available to look up networks by their names.

d_getnent
From d_getnent.U:

This variable conditionally defines "HAS_GETNETENT" if getnetent() is available to look up network names in some data base or another.

d_getnetbyaddr_r
From d_getnetbyaddr_r.U:

This variable conditionally defines the "HAS_GETNETBYADDR_R" symbol, which indicates to the C program that the getnetbyaddr_r() routine is available.

d_getnetbyname_r
From d_getnetbyname_r.U:

This variable conditionally defines the "HAS_GETNETBYNAME_R" symbol, which indicates to the C program that the getnetbyname_r() routine is available.

d_getnetent_r
From d_getnetent_r.U:

This variable conditionally defines the "HAS_GETNETENT_R" symbol, which indicates to the C program that the getnetent_r() routine is available.

d_getnetprotos
From d_getnetprotos.U:

This variable conditionally defines the "HAS_GETNET_PROTOS" symbol, which indicates to the C program that <netdb.h> supplies prototypes for the various getnet*() functions. See also netdbtype.U for probing for various netdb types.

d_getpagsz
From d_getpagsz.U:

This variable conditionally defines "HAS_GETPAGESIZE" if getpagesize() is available to get the system page size.

d_getpbyname
From d_getprotby.U:

This variable conditionally defines the "HAS_GETPROTOBYNAME" symbol, which indicates to the C program that the getprotobyname() routine is available to look up protocols by their name.

d_getpbynumber
From d_getprotby.U:

This variable conditionally defines the "HAS_GETPROTOBYNUMBER" symbol, which indicates to the C program that the getprotobynumber() routine is available to look up protocols by their number.

d_getpent
From d_getpent.U:

This variable conditionally defines "HAS_GETPROTOENT" if getprotoent() is available to look up protocols in some data base or another.

d_getpgid
From d_getpgid.U:

This variable conditionally defines the "HAS_GETPGID" symbol, which indicates to the C program that the getpgid(pid) function is available to get the process group id.

d_getpgrp
From d_getpgrp.U:

This variable conditionally defines "HAS_GETPGRP" if getpgrp() is available to get the current process group.

d_getpgrp2
From d_getpgrp2.U:

This variable conditionally defines the HAS_GETPGRP2 symbol, which indicates to the C program that the getpgrp2() (as in DG/"UX") routine is available to get the current process group.

d_getppid
From d_getppid.U:

This variable conditionally defines the "HAS_GETPPID" symbol, which indicates to the C program that the getppid() routine is available to get the parent process "ID".

d_getprior
From d_getprior.U:

This variable conditionally defines "HAS_GETPRIORITY" if getpriority() is available to get a process's priority.

d_getprotobyname_r
From d_getprotobyname_r.U:

This variable conditionally defines the "HAS_GETPROTOBYNAME_R" symbol, which indicates to the C program that the getprotobyname_r() routine is available.

d_getprotobynumber_r
From d_getprotobynumber_r.U:

This variable conditionally defines the "HAS_GETPROTOBYNUMBER_R" symbol, which indicates to the C program that the getprotobynumber_r() routine is available.

d_getprotoent_r
From d_getprotoent_r.U:

This variable conditionally defines the "HAS_GETPROTOENT_R" symbol, which indicates to the C program that the getprotoent_r() routine is available.

d_getprotoprotos
From d_getprotoprotos.U:

This variable conditionally defines the "HAS_GETPROTO_PROTOS" symbol, which indicates to the C program that <netdb.h> supplies prototypes for the various getproto*() functions. See also netdbtype.U for probing for various netdb types.

d_getprpwnam
From d_getprpwnam.U:

This variable conditionally defines "HAS_GETPRPWNAM" if getprpwnam() is available to retrieve protected (shadow) password entries by name.

d_getpwent
From d_getpwent.U:

This variable conditionally defines the "HAS_GETPWENT" symbol, which indicates to the C program that the getpwent() routine is available for sequential access of the passwd database.

d_getpwent_r
From d_getpwent_r.U:

This variable conditionally defines the "HAS_GETPWENT_R" symbol, which indicates to the C program that the getpwent_r() routine is available.

d_getpwnam_r
From d_getpwnam_r.U:

This variable conditionally defines the "HAS_GETPWNAM_R" symbol, which indicates to the C program that the getpwnam_r() routine is available.

d_getpwuid_r
From d_getpwuid_r.U:

This variable conditionally defines the "HAS_GETPWUID_R" symbol, which indicates to the C program that the getpwuid_r() routine is available.

d_getsbyname
From d_getsrvby.U:

This variable conditionally defines the "HAS_GETSERVBYNAME" symbol, which indicates to the C program that the getservbyname() routine is available to look up services by their name.

d_getsbyport
From d_getsrvby.U:

This variable conditionally defines the "HAS_GETSERVBYPORT" symbol, which indicates to the C program that the getservbyport() routine is available to look up services by their port.

d_getsent
From d_getsent.U:

This variable conditionally defines "HAS_GETSERVENT" if getservent() is available to look up network services in some data base or another.

d_getservbyname_r
From d_getservbyname_r.U:

This variable conditionally defines the "HAS_GETSERVBYNAME_R" symbol, which indicates to the C program that the getservbyname_r() routine is available.

d_getservbyport_r
From d_getservbyport_r.U:

This variable conditionally defines the "HAS_GETSERVBYPORT_R" symbol, which indicates to the C program that the getservbyport_r() routine is available.

d_getservent_r
From d_getservent_r.U:

This variable conditionally defines the "HAS_GETSERVENT_R" symbol, which indicates to the C program that the getservent_r() routine is available.

d_getservprotos
From d_getservprotos.U:

This variable conditionally defines the "HAS_GETSERV_PROTOS" symbol, which indicates to the C program that <netdb.h> supplies prototypes for the various getserv*() functions. See also netdbtype.U for probing for various netdb types.

d_getspnam
From d_getspnam.U:

This variable conditionally defines "HAS_GETSPNAM" if getspnam() is available to retrieve SysV shadow password entries by name.

d_getspnam_r
From d_getspnam_r.U:

This variable conditionally defines the "HAS_GETSPNAM_R" symbol, which indicates to the C program that the getspnam_r() routine is available.

d_gettimeod
From d_ftime.U:

This variable conditionally defines the "HAS_GETTIMEOFDAY" symbol, which indicates that the gettimeofday() system call exists (to obtain a sub-second accuracy clock). You should probably include <sys/resource.h>.

d_gmtime64
From d_timefuncs64.U:

This variable conditionally defines the HAS_GMTIME64 symbol, which indicates to the C program that the gmtime64 () routine is available.

d_gmtime_r
From d_gmtime_r.U:

This variable conditionally defines the "HAS_GMTIME_R" symbol, which indicates to the C program that the gmtime_r() routine is available.

d_gnulibc
From d_gnulibc.U:

Defined if we're dealing with the "GNU" C Library.

d_grpasswd
From i_grp.U:

This variable conditionally defines "GRPASSWD", which indicates that struct group in <grp.h> contains gr_passwd.

d_hasmntopt
From d_hasmntopt.U:

This variable conditionally defines the "HAS_HASMNTOPT" symbol, which indicates to the C program that the hasmntopt() routine is available to query the mount options of file systems.

d_htonl
From d_htonl.U:

This variable conditionally defines "HAS_HTONL" if htonl() and its friends are available to do network order byte swapping.

d_ilogbl
From d_ilogbl.U:

This variable conditionally defines the "HAS_ILOGBL" symbol, which indicates to the C program that the ilogbl() routine is available. If scalbnl is also present we can emulate frexpl.

d_inc_version_list
From inc_version_list.U:

This variable conditionally defines "PERL_INC_VERSION_LIST". It is set to undef when "PERL_INC_VERSION_LIST" is empty.

d_index
From d_strchr.U:

This variable conditionally defines "HAS_INDEX" if index() and rindex() are available for string searching.

d_inetaton
From d_inetaton.U:

This variable conditionally defines the "HAS_INET_ATON" symbol, which indicates to the C program that the inet_aton() function is available to parse "IP" address "dotted-quad" strings.

d_inetntop
From d_inetntop.U:

This variable conditionally defines the "HAS_INETNTOP" symbol, which indicates to the C program that the inet_ntop() function is available.

d_inetpton
From d_inetpton.U:

This variable conditionally defines the "HAS_INETPTON" symbol, which indicates to the C program that the inet_pton() function is available.

d_int64_t
From d_int64_t.U:

This symbol will be defined if the C compiler supports int64_t.

d_isascii
From d_isascii.U:

This variable conditionally defines the "HAS_ISASCII" constant, which indicates to the C program that isascii() is available.

d_isfinite
From d_isfinite.U:

This variable conditionally defines the "HAS_ISFINITE" symbol, which indicates to the C program that the isfinite() routine is available.

d_isinf
From d_isinf.U:

This variable conditionally defines the "HAS_ISINF" symbol, which indicates to the C program that the isinf() routine is available.

d_isnan
From d_isnan.U:

This variable conditionally defines the "HAS_ISNAN" symbol, which indicates to the C program that the isnan() routine is available.

d_isnanl
From d_isnanl.U:

This variable conditionally defines the "HAS_ISNANL" symbol, which indicates to the C program that the isnanl() routine is available.

d_killpg
From d_killpg.U:

This variable conditionally defines the "HAS_KILLPG" symbol, which indicates to the C program that the killpg() routine is available to kill process groups.

d_lchown
From d_lchown.U:

This variable conditionally defines the "HAS_LCHOWN" symbol, which indicates to the C program that the lchown() routine is available to operate on a symbolic link (instead of following the link).

d_ldbl_dig
From d_ldbl_dig.U:

This variable conditionally defines d_ldbl_dig if this system's header files provide "LDBL_DIG", which is the number of significant digits in a long double precision number.

d_libm_lib_version
From d_libm_lib_version.U:

This variable conditionally defines the "LIBM_LIB_VERSION" symbol, which indicates to the C program that math.h defines "_LIB_VERSION" being available in libm

d_link
From d_link.U:

This variable conditionally defines "HAS_LINK" if link() is available to create hard links.

d_localtime64
From d_timefuncs64.U:

This variable conditionally defines the HAS_LOCALTIME64 symbol, which indicates to the C program that the localtime64 () routine is available.

d_localtime_r
From d_localtime_r.U:

This variable conditionally defines the "HAS_LOCALTIME_R" symbol, which indicates to the C program that the localtime_r() routine is available.

d_localtime_r_needs_tzset
From d_localtime_r.U:

This variable conditionally defines the "LOCALTIME_R_NEEDS_TZSET" symbol, which makes us call tzset before localtime_r()

d_locconv
From d_locconv.U:

This variable conditionally defines "HAS_LOCALECONV" if localeconv() is available for numeric and monetary formatting conventions.

d_lockf
From d_lockf.U:

This variable conditionally defines "HAS_LOCKF" if lockf() is available to do file locking.

d_longdbl
From d_longdbl.U:

This variable conditionally defines "HAS_LONG_DOUBLE" if the long double type is supported.

d_longlong
From d_longlong.U:

This variable conditionally defines "HAS_LONG_LONG" if the long long type is supported.

d_lseekproto
From d_lseekproto.U:

This variable conditionally defines the "HAS_LSEEK_PROTO" symbol, which indicates to the C program that the system provides a prototype for the lseek() function. Otherwise, it is up to the program to supply one.

d_lstat
From d_lstat.U:

This variable conditionally defines "HAS_LSTAT" if lstat() is available to do file stats on symbolic links.

d_madvise
From d_madvise.U:

This variable conditionally defines "HAS_MADVISE" if madvise() is available to map a file into memory.

d_malloc_good_size
From d_malloc_size.U:

This symbol, if defined, indicates that the malloc_good_size routine is available for use.

d_malloc_size
From d_malloc_size.U:

This symbol, if defined, indicates that the malloc_size routine is available for use.

d_mblen
From d_mblen.U:

This variable conditionally defines the "HAS_MBLEN" symbol, which indicates to the C program that the mblen() routine is available to find the number of bytes in a multibye character.

d_mbstowcs
From d_mbstowcs.U:

This variable conditionally defines the "HAS_MBSTOWCS" symbol, which indicates to the C program that the mbstowcs() routine is available to convert a multibyte string into a wide character string.

d_mbtowc
From d_mbtowc.U:

This variable conditionally defines the "HAS_MBTOWC" symbol, which indicates to the C program that the mbtowc() routine is available to convert multibyte to a wide character.

d_memchr
From d_memchr.U:

This variable conditionally defines the "HAS_MEMCHR" symbol, which indicates to the C program that the memchr() routine is available to locate characters within a C string.

d_memcmp
From d_memcmp.U:

This variable conditionally defines the "HAS_MEMCMP" symbol, which indicates to the C program that the memcmp() routine is available to compare blocks of memory.

d_memcpy
From d_memcpy.U:

This variable conditionally defines the "HAS_MEMCPY" symbol, which indicates to the C program that the memcpy() routine is available to copy blocks of memory.

d_memmove
From d_memmove.U:

This variable conditionally defines the "HAS_MEMMOVE" symbol, which indicates to the C program that the memmove() routine is available to copy potentatially overlapping blocks of memory.

d_memset
From d_memset.U:

This variable conditionally defines the "HAS_MEMSET" symbol, which indicates to the C program that the memset() routine is available to set blocks of memory.

d_mkdir
From d_mkdir.U:

This variable conditionally defines the "HAS_MKDIR" symbol, which indicates to the C program that the mkdir() routine is available to create directories..

d_mkdtemp
From d_mkdtemp.U:

This variable conditionally defines the "HAS_MKDTEMP" symbol, which indicates to the C program that the mkdtemp() routine is available to exclusively create a uniquely named temporary directory.

d_mkfifo
From d_mkfifo.U:

This variable conditionally defines the "HAS_MKFIFO" symbol, which indicates to the C program that the mkfifo() routine is available.

d_mkstemp
From d_mkstemp.U:

This variable conditionally defines the "HAS_MKSTEMP" symbol, which indicates to the C program that the mkstemp() routine is available to exclusively create and open a uniquely named temporary file.

d_mkstemps
From d_mkstemps.U:

This variable conditionally defines the "HAS_MKSTEMPS" symbol, which indicates to the C program that the mkstemps() routine is available to exclusively create and open a uniquely named (with a suffix) temporary file.

d_mktime
From d_mktime.U:

This variable conditionally defines the "HAS_MKTIME" symbol, which indicates to the C program that the mktime() routine is available.

d_mktime64
From d_timefuncs64.U:

This variable conditionally defines the HAS_MKTIME64 symbol, which indicates to the C program that the mktime64 () routine is available.

d_mmap
From d_mmap.U:

This variable conditionally defines "HAS_MMAP" if mmap() is available to map a file into memory.

d_modfl
From d_modfl.U:

This variable conditionally defines the "HAS_MODFL" symbol, which indicates to the C program that the modfl() routine is available.

d_modfl_pow32_bug
From d_modfl.U:

This variable conditionally defines the HAS_MODFL_POW32_BUG symbol, which indicates that modfl() is broken for long doubles >= pow(2, 32). For example from 4294967303.150000 one would get 4294967302.000000 and 1.150000. The bug has been seen in certain versions of glibc, release 2.2.2 is known to be okay.

d_modflproto
From d_modfl.U:

This symbol, if defined, indicates that the system provides a prototype for the modfl() function. Otherwise, it is up to the program to supply one. C99 says it should be long double modfl(long double, long double *);

d_mprotect
From d_mprotect.U:

This variable conditionally defines "HAS_MPROTECT" if mprotect() is available to modify the access protection of a memory mapped file.

d_msg
From d_msg.U:

This variable conditionally defines the "HAS_MSG" symbol, which indicates that the entire msg*(2) library is present.

d_msg_ctrunc
From d_socket.U:

This variable conditionally defines the "HAS_MSG_CTRUNC" symbol, which indicates that the "MSG_CTRUNC" is available. #ifdef is not enough because it may be an enum, glibc has been known to do this.

d_msg_dontroute
From d_socket.U:

This variable conditionally defines the "HAS_MSG_DONTROUTE" symbol, which indicates that the "MSG_DONTROUTE" is available. #ifdef is not enough because it may be an enum, glibc has been known to do this.

d_msg_oob
From d_socket.U:

This variable conditionally defines the "HAS_MSG_OOB" symbol, which indicates that the "MSG_OOB" is available. #ifdef is not enough because it may be an enum, glibc has been known to do this.

d_msg_peek
From d_socket.U:

This variable conditionally defines the "HAS_MSG_PEEK" symbol, which indicates that the "MSG_PEEK" is available. #ifdef is not enough because it may be an enum, glibc has been known to do this.

d_msg_proxy
From d_socket.U:

This variable conditionally defines the "HAS_MSG_PROXY" symbol, which indicates that the "MSG_PROXY" is available. #ifdef is not enough because it may be an enum, glibc has been known to do this.

d_msgctl
From d_msgctl.U:

This variable conditionally defines the "HAS_MSGCTL" symbol, which indicates to the C program that the msgctl() routine is available.

d_msgget
From d_msgget.U:

This variable conditionally defines the "HAS_MSGGET" symbol, which indicates to the C program that the msgget() routine is available.

d_msghdr_s
From d_msghdr_s.U:

This variable conditionally defines the "HAS_STRUCT_MSGHDR" symbol, which indicates that the struct msghdr is supported.

d_msgrcv
From d_msgrcv.U:

This variable conditionally defines the "HAS_MSGRCV" symbol, which indicates to the C program that the msgrcv() routine is available.

d_msgsnd
From d_msgsnd.U:

This variable conditionally defines the "HAS_MSGSND" symbol, which indicates to the C program that the msgsnd() routine is available.

d_msync
From d_msync.U:

This variable conditionally defines "HAS_MSYNC" if msync() is available to synchronize a mapped file.

d_munmap
From d_munmap.U:

This variable conditionally defines "HAS_MUNMAP" if munmap() is available to unmap a region mapped by mmap().

d_mymalloc
From mallocsrc.U:

This variable conditionally defines "MYMALLOC" in case other parts of the source want to take special action if "MYMALLOC" is used. This may include different sorts of profiling or error detection.

d_ndbm
From i_ndbm.U:

This variable conditionally defines the "HAS_NDBM" symbol, which indicates that both the ndbm.h include file and an appropriate ndbm library exist. Consult the different i_*ndbm variables to find out the actual include location. Sometimes, a system has the header file but not the library. This variable will only be set if the system has both.

d_ndbm_h_uses_prototypes
From i_ndbm.U:

This variable conditionally defines the "NDBM_H_USES_PROTOTYPES" symbol, which indicates that the ndbm.h include file uses real "ANSI" C prototypes instead of K&R style function declarations. K&R style declarations are unsupported in C++, so the include file requires special handling when using a C++ compiler and this variable is undefined. Consult the different d_*ndbm_h_uses_prototypes variables to get the same information for alternative ndbm.h include files.

d_nice
From d_nice.U:

This variable conditionally defines the "HAS_NICE" symbol, which indicates to the C program that the nice() routine is available.

d_nl_langinfo
From d_nl_langinfo.U:

This variable conditionally defines the "HAS_NL_LANGINFO" symbol, which indicates to the C program that the nl_langinfo() routine is available.

d_nv_preserves_uv
From perlxv.U:

This variable indicates whether a variable of type nvtype can preserve all the bits a variable of type uvtype.

d_nv_zero_is_allbits_zero
From perlxv.U:

This variable indicates whether a variable of type nvtype stores 0.0 in memory as all bits zero.

d_off64_t
From d_off64_t.U:

This symbol will be defined if the C compiler supports off64_t.

d_old_pthread_create_joinable
From d_pthrattrj.U:

This variable conditionally defines pthread_create_joinable. undef if pthread.h defines "PTHREAD_CREATE_JOINABLE".

d_oldpthreads
From usethreads.U:

This variable conditionally defines the "OLD_PTHREADS_API" symbol, and indicates that Perl should be built to use the old draft "POSIX" threads "API". This is only potentially meaningful if usethreads is set.

d_oldsock
From d_socket.U:

This variable conditionally defines the "OLDSOCKET" symbol, which indicates that the "BSD" socket interface is based on 4.1c and not 4.2.

d_open3
From d_open3.U:

This variable conditionally defines the HAS_OPEN3 manifest constant, which indicates to the C program that the 3 argument version of the open(2) function is available.

d_pathconf
From d_pathconf.U:

This variable conditionally defines the "HAS_PATHCONF" symbol, which indicates to the C program that the pathconf() routine is available to determine file-system related limits and options associated with a given filename.

d_pause
From d_pause.U:

This variable conditionally defines the "HAS_PAUSE" symbol, which indicates to the C program that the pause() routine is available to suspend a process until a signal is received.

d_perl_otherlibdirs
From otherlibdirs.U:

This variable conditionally defines "PERL_OTHERLIBDIRS", which contains a colon-separated set of paths for the perl binary to include in @"INC". See also otherlibdirs.

d_phostname
From d_gethname.U:

This variable conditionally defines the "HAS_PHOSTNAME" symbol, which contains the shell command which, when fed to popen(), may be used to derive the host name.

d_pipe
From d_pipe.U:

This variable conditionally defines the "HAS_PIPE" symbol, which indicates to the C program that the pipe() routine is available to create an inter-process channel.

d_poll
From d_poll.U:

This variable conditionally defines the "HAS_POLL" symbol, which indicates to the C program that the poll() routine is available to poll active file descriptors.

d_portable
From d_portable.U:

This variable conditionally defines the "PORTABLE" symbol, which indicates to the C program that it should not assume that it is running on the machine it was compiled on.

d_PRId64
From quadfio.U:

This variable conditionally defines the PERL_PRId64 symbol, which indiciates that stdio has a symbol to print 64-bit decimal numbers.

d_PRIeldbl
From longdblfio.U:

This variable conditionally defines the PERL_PRIfldbl symbol, which indiciates that stdio has a symbol to print long doubles.

d_PRIEUldbl
From longdblfio.U:

This variable conditionally defines the PERL_PRIfldbl symbol, which indiciates that stdio has a symbol to print long doubles. The "U" in the name is to separate this from d_PRIeldbl so that even case-blind systems can see the difference.

d_PRIfldbl
From longdblfio.U:

This variable conditionally defines the PERL_PRIfldbl symbol, which indiciates that stdio has a symbol to print long doubles.

d_PRIFUldbl
From longdblfio.U:

This variable conditionally defines the PERL_PRIfldbl symbol, which indiciates that stdio has a symbol to print long doubles. The "U" in the name is to separate this from d_PRIfldbl so that even case-blind systems can see the difference.

d_PRIgldbl
From longdblfio.U:

This variable conditionally defines the PERL_PRIfldbl symbol, which indiciates that stdio has a symbol to print long doubles.

d_PRIGUldbl
From longdblfio.U:

This variable conditionally defines the PERL_PRIfldbl symbol, which indiciates that stdio has a symbol to print long doubles. The "U" in the name is to separate this from d_PRIgldbl so that even case-blind systems can see the difference.

d_PRIi64
From quadfio.U:

This variable conditionally defines the PERL_PRIi64 symbol, which indiciates that stdio has a symbol to print 64-bit decimal numbers.

d_printf_format_null
From d_attribut.U:

This variable conditionally defines "PRINTF_FORMAT_NULL_OK", which indicates the C compiler allows printf-like formats to be null.

d_PRIo64
From quadfio.U:

This variable conditionally defines the PERL_PRIo64 symbol, which indiciates that stdio has a symbol to print 64-bit octal numbers.

d_PRIu64
From quadfio.U:

This variable conditionally defines the PERL_PRIu64 symbol, which indiciates that stdio has a symbol to print 64-bit unsigned decimal numbers.

d_PRIx64
From quadfio.U:

This variable conditionally defines the PERL_PRIx64 symbol, which indiciates that stdio has a symbol to print 64-bit hexadecimal numbers.

d_PRIXU64
From quadfio.U:

This variable conditionally defines the PERL_PRIXU64 symbol, which indiciates that stdio has a symbol to print 64-bit hExADECimAl numbers. The "U" in the name is to separate this from d_PRIx64 so that even case-blind systems can see the difference.

d_procselfexe
From d_procselfexe.U:

Defined if $procselfexe is symlink to the absolute pathname of the executing program.

d_pseudofork
From d_vfork.U:

This variable conditionally defines the "HAS_PSEUDOFORK" symbol, which indicates that an emulation of the fork routine is available.

d_pthread_atfork
From d_pthread_atfork.U:

This variable conditionally defines the "HAS_PTHREAD_ATFORK" symbol, which indicates to the C program that the pthread_atfork() routine is available.

d_pthread_attr_setscope
From d_pthread_attr_ss.U:

This variable conditionally defines "HAS_PTHREAD_ATTR_SETSCOPE" if pthread_attr_setscope() is available to set the contention scope attribute of a thread attribute object.

d_pthread_yield
From d_pthread_y.U:

This variable conditionally defines the "HAS_PTHREAD_YIELD" symbol if the pthread_yield routine is available to yield the execution of the current thread.

d_pwage
From i_pwd.U:

This variable conditionally defines "PWAGE", which indicates that struct passwd contains pw_age.

d_pwchange
From i_pwd.U:

This variable conditionally defines "PWCHANGE", which indicates that struct passwd contains pw_change.

d_pwclass
From i_pwd.U:

This variable conditionally defines "PWCLASS", which indicates that struct passwd contains pw_class.

d_pwcomment
From i_pwd.U:

This variable conditionally defines "PWCOMMENT", which indicates that struct passwd contains pw_comment.

d_pwexpire
From i_pwd.U:

This variable conditionally defines "PWEXPIRE", which indicates that struct passwd contains pw_expire.

d_pwgecos
From i_pwd.U:

This variable conditionally defines "PWGECOS", which indicates that struct passwd contains pw_gecos.

d_pwpasswd
From i_pwd.U:

This variable conditionally defines "PWPASSWD", which indicates that struct passwd contains pw_passwd.

d_pwquota
From i_pwd.U:

This variable conditionally defines "PWQUOTA", which indicates that struct passwd contains pw_quota.

d_qgcvt
From d_qgcvt.U:

This variable conditionally defines the "HAS_QGCVT" symbol, which indicates to the C program that the qgcvt() routine is available.

d_quad
From quadtype.U:

This variable, if defined, tells that there's a 64-bit integer type, quadtype.

d_random_r
From d_random_r.U:

This variable conditionally defines the "HAS_RANDOM_R" symbol, which indicates to the C program that the random_r() routine is available.

d_readdir
From d_readdir.U:

This variable conditionally defines "HAS_READDIR" if readdir() is available to read directory entries.

d_readdir64_r
From d_readdir64_r.U:

This variable conditionally defines the HAS_READDIR64_R symbol, which indicates to the C program that the readdir64_r() routine is available.

d_readdir_r
From d_readdir_r.U:

This variable conditionally defines the "HAS_READDIR_R" symbol, which indicates to the C program that the readdir_r() routine is available.

d_readlink
From d_readlink.U:

This variable conditionally defines the "HAS_READLINK" symbol, which indicates to the C program that the readlink() routine is available to read the value of a symbolic link.

d_readv
From d_readv.U:

This variable conditionally defines the "HAS_READV" symbol, which indicates to the C program that the readv() routine is available.

d_recvmsg
From d_recvmsg.U:

This variable conditionally defines the "HAS_RECVMSG" symbol, which indicates to the C program that the recvmsg() routine is available.

d_rename
From d_rename.U:

This variable conditionally defines the "HAS_RENAME" symbol, which indicates to the C program that the rename() routine is available to rename files.

d_rewinddir
From d_readdir.U:

This variable conditionally defines "HAS_REWINDDIR" if rewinddir() is available.

d_rmdir
From d_rmdir.U:

This variable conditionally defines "HAS_RMDIR" if rmdir() is available to remove directories.

d_safebcpy
From d_safebcpy.U:

This variable conditionally defines the "HAS_SAFE_BCOPY" symbol if the bcopy() routine can do overlapping copies. Normally, you should probably use memmove().

d_safemcpy
From d_safemcpy.U:

This variable conditionally defines the "HAS_SAFE_MEMCPY" symbol if the memcpy() routine can do overlapping copies. For overlapping copies, memmove() should be used, if available.

d_sanemcmp
From d_sanemcmp.U:

This variable conditionally defines the "HAS_SANE_MEMCMP" symbol if the memcpy() routine is available and can be used to compare relative magnitudes of chars with their high bits set.

d_sbrkproto
From d_sbrkproto.U:

This variable conditionally defines the "HAS_SBRK_PROTO" symbol, which indicates to the C program that the system provides a prototype for the sbrk() function. Otherwise, it is up to the program to supply one.

d_scalbnl
From d_scalbnl.U:

This variable conditionally defines the "HAS_SCALBNL" symbol, which indicates to the C program that the scalbnl() routine is available. If ilogbl is also present we can emulate frexpl.

d_sched_yield
From d_pthread_y.U:

This variable conditionally defines the "HAS_SCHED_YIELD" symbol if the sched_yield routine is available to yield the execution of the current thread.

d_scm_rights
From d_socket.U:

This variable conditionally defines the "HAS_SCM_RIGHTS" symbol, which indicates that the "SCM_RIGHTS" is available. #ifdef is not enough because it may be an enum, glibc has been known to do this.

d_SCNfldbl
From longdblfio.U:

This variable conditionally defines the PERL_PRIfldbl symbol, which indiciates that stdio has a symbol to scan long doubles.

d_seekdir
From d_readdir.U:

This variable conditionally defines "HAS_SEEKDIR" if seekdir() is available.

d_select
From d_select.U:

This variable conditionally defines "HAS_SELECT" if select() is available to select active file descriptors. A <sys/time.h> inclusion may be necessary for the timeout field.

d_sem
From d_sem.U:

This variable conditionally defines the "HAS_SEM" symbol, which indicates that the entire sem*(2) library is present.

d_semctl
From d_semctl.U:

This variable conditionally defines the "HAS_SEMCTL" symbol, which indicates to the C program that the semctl() routine is available.

d_semctl_semid_ds
From d_union_semun.U:

This variable conditionally defines "USE_SEMCTL_SEMID_DS", which indicates that struct semid_ds * is to be used for semctl "IPC_STAT".

d_semctl_semun
From d_union_semun.U:

This variable conditionally defines "USE_SEMCTL_SEMUN", which indicates that union semun is to be used for semctl "IPC_STAT".

d_semget
From d_semget.U:

This variable conditionally defines the "HAS_SEMGET" symbol, which indicates to the C program that the semget() routine is available.

d_semop
From d_semop.U:

This variable conditionally defines the "HAS_SEMOP" symbol, which indicates to the C program that the semop() routine is available.

d_sendmsg
From d_sendmsg.U:

This variable conditionally defines the "HAS_SENDMSG" symbol, which indicates to the C program that the sendmsg() routine is available.

d_setegid
From d_setegid.U:

This variable conditionally defines the "HAS_SETEGID" symbol, which indicates to the C program that the setegid() routine is available to change the effective gid of the current program.

d_seteuid
From d_seteuid.U:

This variable conditionally defines the "HAS_SETEUID" symbol, which indicates to the C program that the seteuid() routine is available to change the effective uid of the current program.

d_setgrent
From d_setgrent.U:

This variable conditionally defines the "HAS_SETGRENT" symbol, which indicates to the C program that the setgrent() routine is available for initializing sequential access to the group database.

d_setgrent_r
From d_setgrent_r.U:

This variable conditionally defines the "HAS_SETGRENT_R" symbol, which indicates to the C program that the setgrent_r() routine is available.

d_setgrps
From d_setgrps.U:

This variable conditionally defines the "HAS_SETGROUPS" symbol, which indicates to the C program that the setgroups() routine is available to set the list of process groups.

d_sethent
From d_sethent.U:

This variable conditionally defines "HAS_SETHOSTENT" if sethostent() is available.

d_sethostent_r
From d_sethostent_r.U:

This variable conditionally defines the "HAS_SETHOSTENT_R" symbol, which indicates to the C program that the sethostent_r() routine is available.

d_setitimer
From d_setitimer.U:

This variable conditionally defines the "HAS_SETITIMER" symbol, which indicates to the C program that the setitimer() routine is available.

d_setlinebuf
From d_setlnbuf.U:

This variable conditionally defines the "HAS_SETLINEBUF" symbol, which indicates to the C program that the setlinebuf() routine is available to change stderr or stdout from block-buffered or unbuffered to a line-buffered mode.

d_setlocale
From d_setlocale.U:

This variable conditionally defines "HAS_SETLOCALE" if setlocale() is available to handle locale-specific ctype implementations.

d_setlocale_r
From d_setlocale_r.U:

This variable conditionally defines the "HAS_SETLOCALE_R" symbol, which indicates to the C program that the setlocale_r() routine is available.

d_setnent
From d_setnent.U:

This variable conditionally defines "HAS_SETNETENT" if setnetent() is available.

d_setnetent_r
From d_setnetent_r.U:

This variable conditionally defines the "HAS_SETNETENT_R" symbol, which indicates to the C program that the setnetent_r() routine is available.

d_setpent
From d_setpent.U:

This variable conditionally defines "HAS_SETPROTOENT" if setprotoent() is available.

d_setpgid
From d_setpgid.U:

This variable conditionally defines the "HAS_SETPGID" symbol if the setpgid(pid, gpid) function is available to set process group "ID".

d_setpgrp
From d_setpgrp.U:

This variable conditionally defines "HAS_SETPGRP" if setpgrp() is available to set the current process group.

d_setpgrp2
From d_setpgrp2.U:

This variable conditionally defines the HAS_SETPGRP2 symbol, which indicates to the C program that the setpgrp2() (as in DG/"UX") routine is available to set the current process group.

d_setprior
From d_setprior.U:

This variable conditionally defines "HAS_SETPRIORITY" if setpriority() is available to set a process's priority.

d_setproctitle
From d_setproctitle.U:

This variable conditionally defines the "HAS_SETPROCTITLE" symbol, which indicates to the C program that the setproctitle() routine is available.

d_setprotoent_r
From d_setprotoent_r.U:

This variable conditionally defines the "HAS_SETPROTOENT_R" symbol, which indicates to the C program that the setprotoent_r() routine is available.

d_setpwent
From d_setpwent.U:

This variable conditionally defines the "HAS_SETPWENT" symbol, which indicates to the C program that the setpwent() routine is available for initializing sequential access to the passwd database.

d_setpwent_r
From d_setpwent_r.U:

This variable conditionally defines the "HAS_SETPWENT_R" symbol, which indicates to the C program that the setpwent_r() routine is available.

d_setregid
From d_setregid.U:

This variable conditionally defines "HAS_SETREGID" if setregid() is available to change the real and effective gid of the current process.

d_setresgid
From d_setregid.U:

This variable conditionally defines "HAS_SETRESGID" if setresgid() is available to change the real, effective and saved gid of the current process.

d_setresuid
From d_setreuid.U:

This variable conditionally defines "HAS_SETREUID" if setresuid() is available to change the real, effective and saved uid of the current process.

d_setreuid
From d_setreuid.U:

This variable conditionally defines "HAS_SETREUID" if setreuid() is available to change the real and effective uid of the current process.

d_setrgid
From d_setrgid.U:

This variable conditionally defines the "HAS_SETRGID" symbol, which indicates to the C program that the setrgid() routine is available to change the real gid of the current program.

d_setruid
From d_setruid.U:

This variable conditionally defines the "HAS_SETRUID" symbol, which indicates to the C program that the setruid() routine is available to change the real uid of the current program.

d_setsent
From d_setsent.U:

This variable conditionally defines "HAS_SETSERVENT" if setservent() is available.

d_setservent_r
From d_setservent_r.U:

This variable conditionally defines the "HAS_SETSERVENT_R" symbol, which indicates to the C program that the setservent_r() routine is available.

d_setsid
From d_setsid.U:

This variable conditionally defines "HAS_SETSID" if setsid() is available to set the process group "ID".

d_setvbuf
From d_setvbuf.U:

This variable conditionally defines the "HAS_SETVBUF" symbol, which indicates to the C program that the setvbuf() routine is available to change buffering on an open stdio stream.

d_sfio
From d_sfio.U:

This variable conditionally defines the "USE_SFIO" symbol, and indicates whether sfio is available (and should be used).

d_shm
From d_shm.U:

This variable conditionally defines the "HAS_SHM" symbol, which indicates that the entire shm*(2) library is present.

d_shmat
From d_shmat.U:

This variable conditionally defines the "HAS_SHMAT" symbol, which indicates to the C program that the shmat() routine is available.

d_shmatprototype
From d_shmat.U:

This variable conditionally defines the "HAS_SHMAT_PROTOTYPE" symbol, which indicates that sys/shm.h has a prototype for shmat.

d_shmctl
From d_shmctl.U:

This variable conditionally defines the "HAS_SHMCTL" symbol, which indicates to the C program that the shmctl() routine is available.

d_shmdt
From d_shmdt.U:

This variable conditionally defines the "HAS_SHMDT" symbol, which indicates to the C program that the shmdt() routine is available.

d_shmget
From d_shmget.U:

This variable conditionally defines the "HAS_SHMGET" symbol, which indicates to the C program that the shmget() routine is available.

d_sigaction
From d_sigaction.U:

This variable conditionally defines the "HAS_SIGACTION" symbol, which indicates that the Vr4 sigaction() routine is available.

d_signbit
From d_signbit.U:

This variable conditionally defines the "HAS_SIGNBIT" symbol, which indicates to the C program that the signbit() routine is available and safe to use with perl's intern "NV" type.

d_sigprocmask
From d_sigprocmask.U:

This variable conditionally defines "HAS_SIGPROCMASK" if sigprocmask() is available to examine or change the signal mask of the calling process.

d_sigsetjmp
From d_sigsetjmp.U:

This variable conditionally defines the "HAS_SIGSETJMP" symbol, which indicates that the sigsetjmp() routine is available to call setjmp() and optionally save the process's signal mask.

d_sitearch
From sitearch.U:

This variable conditionally defines "SITEARCH" to hold the pathname of architecture-dependent library files for $package. If $sitearch is the same as $archlib, then this is set to undef.

d_snprintf
From d_snprintf.U:

This variable conditionally defines the "HAS_SNPRINTF" symbol, which indicates to the C program that the snprintf () library function is available.

d_sockatmark
From d_sockatmark.U:

This variable conditionally defines the "HAS_SOCKATMARK" symbol, which indicates to the C program that the sockatmark() routine is available.

d_sockatmarkproto
From d_sockatmarkproto.U:

This variable conditionally defines the "HAS_SOCKATMARK_PROTO" symbol, which indicates to the C program that the system provides a prototype for the sockatmark() function. Otherwise, it is up to the program to supply one.

d_socket
From d_socket.U:

This variable conditionally defines "HAS_SOCKET", which indicates that the "BSD" socket interface is supported.

d_socklen_t
From d_socklen_t.U:

This symbol will be defined if the C compiler supports socklen_t.

d_sockpair
From d_socket.U:

This variable conditionally defines the "HAS_SOCKETPAIR" symbol, which indicates that the "BSD" socketpair() is supported.

d_socks5_init
From d_socks5_init.U:

This variable conditionally defines the HAS_SOCKS5_INIT symbol, which indicates to the C program that the socks5_init() routine is available.

d_sprintf_returns_strlen
From d_sprintf_len.U:

This variable defines whether sprintf returns the length of the string (as per the "ANSI" spec). Some C libraries retain compatibility with pre-"ANSI" C and return a pointer to the passed in buffer; for these this variable will be undef.

d_sqrtl
From d_sqrtl.U:

This variable conditionally defines the "HAS_SQRTL" symbol, which indicates to the C program that the sqrtl() routine is available.

d_srand48_r
From d_srand48_r.U:

This variable conditionally defines the HAS_SRAND48_R symbol, which indicates to the C program that the srand48_r() routine is available.

d_srandom_r
From d_srandom_r.U:

This variable conditionally defines the "HAS_SRANDOM_R" symbol, which indicates to the C program that the srandom_r() routine is available.

d_sresgproto
From d_sresgproto.U:

This variable conditionally defines the "HAS_SETRESGID_PROTO" symbol, which indicates to the C program that the system provides a prototype for the setresgid() function. Otherwise, it is up to the program to supply one.

d_sresuproto
From d_sresuproto.U:

This variable conditionally defines the "HAS_SETRESUID_PROTO" symbol, which indicates to the C program that the system provides a prototype for the setresuid() function. Otherwise, it is up to the program to supply one.

d_statblks
From d_statblks.U:

This variable conditionally defines "USE_STAT_BLOCKS" if this system has a stat structure declaring st_blksize and st_blocks.

d_statfs_f_flags
From d_statfs_f_flags.U:

This variable conditionally defines the "HAS_STRUCT_STATFS_F_FLAGS" symbol, which indicates to struct statfs from has f_flags member. This kind of struct statfs is coming from sys/mount.h ("BSD"), not from sys/statfs.h ("SYSV").

d_statfs_s
From d_statfs_s.U:

This variable conditionally defines the "HAS_STRUCT_STATFS" symbol, which indicates that the struct statfs is supported.

d_statvfs
From d_statvfs.U:

This variable conditionally defines the "HAS_STATVFS" symbol, which indicates to the C program that the statvfs() routine is available.

d_stdio_cnt_lval
From d_stdstdio.U:

This variable conditionally defines "STDIO_CNT_LVALUE" if the "FILE_cnt" macro can be used as an lvalue.

d_stdio_ptr_lval
From d_stdstdio.U:

This variable conditionally defines "STDIO_PTR_LVALUE" if the "FILE_ptr" macro can be used as an lvalue.

d_stdio_ptr_lval_nochange_cnt
From d_stdstdio.U:

This symbol is defined if using the "FILE_ptr" macro as an lvalue to increase the pointer by n leaves File_cnt(fp) unchanged.

d_stdio_ptr_lval_sets_cnt
From d_stdstdio.U:

This symbol is defined if using the "FILE_ptr" macro as an lvalue to increase the pointer by n has the side effect of decreasing the value of File_cnt(fp) by n.

d_stdio_stream_array
From stdio_streams.U:

This variable tells whether there is an array holding the stdio streams.

d_stdiobase
From d_stdstdio.U:

This variable conditionally defines "USE_STDIO_BASE" if this system has a "FILE" structure declaring a usable _base field (or equivalent) in stdio.h.

d_stdstdio
From d_stdstdio.U:

This variable conditionally defines "USE_STDIO_PTR" if this system has a "FILE" structure declaring usable _ptr and _cnt fields (or equivalent) in stdio.h.

d_strchr
From d_strchr.U:

This variable conditionally defines "HAS_STRCHR" if strchr() and strrchr() are available for string searching.

d_strcoll
From d_strcoll.U:

This variable conditionally defines "HAS_STRCOLL" if strcoll() is available to compare strings using collating information.

d_strctcpy
From d_strctcpy.U:

This variable conditionally defines the "USE_STRUCT_COPY" symbol, which indicates to the C program that this C compiler knows how to copy structures.

d_strerrm
From d_strerror.U:

This variable holds what Strerrr is defined as to translate an error code condition into an error message string. It could be "strerror" or a more "complex" macro emulating strrror with sys_errlist[], or the "unknown" string when both strerror and sys_errlist are missing.

d_strerror
From d_strerror.U:

This variable conditionally defines "HAS_STRERROR" if strerror() is available to translate error numbers to strings.

d_strerror_r
From d_strerror_r.U:

This variable conditionally defines the "HAS_STRERROR_R" symbol, which indicates to the C program that the strerror_r() routine is available.

d_strftime
From d_strftime.U:

This variable conditionally defines the "HAS_STRFTIME" symbol, which indicates to the C program that the strftime() routine is available.

d_strlcat
From d_strlcat.U:

This variable conditionally defines the "HAS_STRLCAT" symbol, which indicates to the C program that the strlcat () routine is available.

d_strlcpy
From d_strlcpy.U:

This variable conditionally defines the "HAS_STRLCPY" symbol, which indicates to the C program that the strlcpy () routine is available.

d_strtod
From d_strtod.U:

This variable conditionally defines the "HAS_STRTOD" symbol, which indicates to the C program that the strtod() routine is available to provide better numeric string conversion than atof().

d_strtol
From d_strtol.U:

This variable conditionally defines the "HAS_STRTOL" symbol, which indicates to the C program that the strtol() routine is available to provide better numeric string conversion than atoi() and friends.

d_strtold
From d_strtold.U:

This variable conditionally defines the "HAS_STRTOLD" symbol, which indicates to the C program that the strtold() routine is available.

d_strtoll
From d_strtoll.U:

This variable conditionally defines the "HAS_STRTOLL" symbol, which indicates to the C program that the strtoll() routine is available.

d_strtoq
From d_strtoq.U:

This variable conditionally defines the "HAS_STRTOQ" symbol, which indicates to the C program that the strtoq() routine is available.

d_strtoul
From d_strtoul.U:

This variable conditionally defines the "HAS_STRTOUL" symbol, which indicates to the C program that the strtoul() routine is available to provide conversion of strings to unsigned long.

d_strtoull
From d_strtoull.U:

This variable conditionally defines the "HAS_STRTOULL" symbol, which indicates to the C program that the strtoull() routine is available.

d_strtouq
From d_strtouq.U:

This variable conditionally defines the "HAS_STRTOUQ" symbol, which indicates to the C program that the strtouq() routine is available.

d_strxfrm
From d_strxfrm.U:

This variable conditionally defines "HAS_STRXFRM" if strxfrm() is available to transform strings.

d_suidsafe
From d_dosuid.U:

This variable conditionally defines "SETUID_SCRIPTS_ARE_SECURE_NOW" if setuid scripts can be secure. This test looks in /dev/fd/.

d_symlink
From d_symlink.U:

This variable conditionally defines the "HAS_SYMLINK" symbol, which indicates to the C program that the symlink() routine is available to create symbolic links.

d_syscall
From d_syscall.U:

This variable conditionally defines "HAS_SYSCALL" if syscall() is available call arbitrary system calls.

d_syscallproto
From d_syscallproto.U:

This variable conditionally defines the "HAS_SYSCALL_PROTO" symbol, which indicates to the C program that the system provides a prototype for the syscall() function. Otherwise, it is up to the program to supply one.

d_sysconf
From d_sysconf.U:

This variable conditionally defines the "HAS_SYSCONF" symbol, which indicates to the C program that the sysconf() routine is available to determine system related limits and options.

d_sysernlst
From d_strerror.U:

This variable conditionally defines "HAS_SYS_ERRNOLIST" if sys_errnolist[] is available to translate error numbers to the symbolic name.

d_syserrlst
From d_strerror.U:

This variable conditionally defines "HAS_SYS_ERRLIST" if sys_errlist[] is available to translate error numbers to strings.

d_system
From d_system.U:

This variable conditionally defines "HAS_SYSTEM" if system() is available to issue a shell command.

d_tcgetpgrp
From d_tcgtpgrp.U:

This variable conditionally defines the "HAS_TCGETPGRP" symbol, which indicates to the C program that the tcgetpgrp() routine is available. to get foreground process group "ID".

d_tcsetpgrp
From d_tcstpgrp.U:

This variable conditionally defines the "HAS_TCSETPGRP" symbol, which indicates to the C program that the tcsetpgrp() routine is available to set foreground process group "ID".

d_telldir
From d_readdir.U:

This variable conditionally defines "HAS_TELLDIR" if telldir() is available.

d_telldirproto
From d_telldirproto.U:

This variable conditionally defines the "HAS_TELLDIR_PROTO" symbol, which indicates to the C program that the system provides a prototype for the telldir() function. Otherwise, it is up to the program to supply one.

d_time
From d_time.U:

This variable conditionally defines the "HAS_TIME" symbol, which indicates that the time() routine exists. The time() routine is normaly provided on "UNIX" systems.

d_timegm
From d_timegm.U:

This variable conditionally defines the "HAS_TIMEGM" symbol, which indicates to the C program that the timegm () routine is available.

d_times
From d_times.U:

This variable conditionally defines the "HAS_TIMES" symbol, which indicates that the times() routine exists. The times() routine is normaly provided on "UNIX" systems. You may have to include <sys/times.h>.

d_tm_tm_gmtoff
From i_time.U:

This variable conditionally defines "HAS_TM_TM_GMTOFF", which indicates indicates to the C program that the struct tm has the tm_gmtoff field.

d_tm_tm_zone
From i_time.U:

This variable conditionally defines "HAS_TM_TM_ZONE", which indicates indicates to the C program that the struct tm has the tm_zone field.

d_tmpnam_r
From d_tmpnam_r.U:

This variable conditionally defines the "HAS_TMPNAM_R" symbol, which indicates to the C program that the tmpnam_r() routine is available.

d_truncate
From d_truncate.U:

This variable conditionally defines "HAS_TRUNCATE" if truncate() is available to truncate files.

d_ttyname_r
From d_ttyname_r.U:

This variable conditionally defines the "HAS_TTYNAME_R" symbol, which indicates to the C program that the ttyname_r() routine is available.

d_tzname
From d_tzname.U:

This variable conditionally defines "HAS_TZNAME" if tzname[] is available to access timezone names.

d_u32align
From d_u32align.U:

This variable tells whether you must access character data through U32-aligned pointers.

d_ualarm
From d_ualarm.U:

This variable conditionally defines the "HAS_UALARM" symbol, which indicates to the C program that the ualarm() routine is available.

d_umask
From d_umask.U:

This variable conditionally defines the "HAS_UMASK" symbol, which indicates to the C program that the umask() routine is available. to set and get the value of the file creation mask.

d_uname
From d_gethname.U:

This variable conditionally defines the "HAS_UNAME" symbol, which indicates to the C program that the uname() routine may be used to derive the host name.

d_union_semun
From d_union_semun.U:

This variable conditionally defines "HAS_UNION_SEMUN" if the union semun is defined by including <sys/sem.h>.

d_unordered
From d_unordered.U:

This variable conditionally defines the "HAS_UNORDERED" symbol, which indicates to the C program that the unordered() routine is available.

d_unsetenv
From d_unsetenv.U:

This variable conditionally defines the "HAS_UNSETENV" symbol, which indicates to the C program that the unsetenv () routine is available.

d_usleep
From d_usleep.U:

This variable conditionally defines "HAS_USLEEP" if usleep() is available to do high granularity sleeps.

d_usleepproto
From d_usleepproto.U:

This variable conditionally defines the "HAS_USLEEP_PROTO" symbol, which indicates to the C program that the system provides a prototype for the usleep() function. Otherwise, it is up to the program to supply one.

d_ustat
From d_ustat.U:

This variable conditionally defines "HAS_USTAT" if ustat() is available to query file system statistics by dev_t.

d_vendorarch
From vendorarch.U:

This variable conditionally defined "PERL_VENDORARCH".

d_vendorbin
From vendorbin.U:

This variable conditionally defines "PERL_VENDORBIN".

d_vendorlib
From vendorlib.U:

This variable conditionally defines "PERL_VENDORLIB".

d_vendorscript
From vendorscript.U:

This variable conditionally defines "PERL_VENDORSCRIPT".

d_vfork
From d_vfork.U:

This variable conditionally defines the "HAS_VFORK" symbol, which indicates the vfork() routine is available.

d_void_closedir
From d_closedir.U:

This variable conditionally defines "VOID_CLOSEDIR" if closedir() does not return a value.

d_voidsig
From d_voidsig.U:

This variable conditionally defines "VOIDSIG" if this system declares ``void (*signal(...))()'' in signal.h. The old way was to declare it as ``int (*signal(...))()''.

d_voidtty
From i_sysioctl.U:

This variable conditionally defines "USE_IOCNOTTY" to indicate that the ioctl() call with "TIOCNOTTY" should be used to void tty association. Otherwise (on "USG" probably), it is enough to close the standard file decriptors and do a setpgrp().

d_volatile
From d_volatile.U:

This variable conditionally defines the "HASVOLATILE" symbol, which indicates to the C program that this C compiler knows about the volatile declaration.

d_vprintf
From d_vprintf.U:

This variable conditionally defines the "HAS_VPRINTF" symbol, which indicates to the C program that the vprintf() routine is available to printf with a pointer to an argument list.

d_vsnprintf
From d_snprintf.U:

This variable conditionally defines the "HAS_VSNPRINTF" symbol, which indicates to the C program that the vsnprintf () library function is available.

d_wait4
From d_wait4.U:

This variable conditionally defines the HAS_WAIT4 symbol, which indicates the wait4() routine is available.

d_waitpid
From d_waitpid.U:

This variable conditionally defines "HAS_WAITPID" if waitpid() is available to wait for child process.

d_wcstombs
From d_wcstombs.U:

This variable conditionally defines the "HAS_WCSTOMBS" symbol, which indicates to the C program that the wcstombs() routine is available to convert wide character strings to multibyte strings.

d_wctomb
From d_wctomb.U:

This variable conditionally defines the "HAS_WCTOMB" symbol, which indicates to the C program that the wctomb() routine is available to convert a wide character to a multibyte.

d_writev
From d_writev.U:

This variable conditionally defines the "HAS_WRITEV" symbol, which indicates to the C program that the writev() routine is available.

d_xenix
From Guess.U:

This variable conditionally defines the symbol "XENIX", which alerts the C program that it runs under Xenix.

date
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the date program. After Configure runs, the value is reset to a plain "date" and is not useful.

db_hashtype
From i_db.U:

This variable contains the type of the hash structure element in the <db.h> header file. In older versions of "DB", it was int, while in newer ones it is u_int32_t.

db_prefixtype
From i_db.U:

This variable contains the type of the prefix structure element in the <db.h> header file. In older versions of "DB", it was int, while in newer ones it is size_t.

db_version_major
From i_db.U:

This variable contains the major version number of Berkeley "DB" found in the <db.h> header file.

db_version_minor
From i_db.U:

This variable contains the minor version number of Berkeley "DB" found in the <db.h> header file. For "DB" version 1 this is always 0.

db_version_patch
From i_db.U:

This variable contains the patch version number of Berkeley "DB" found in the <db.h> header file. For "DB" version 1 this is always 0.

defvoidused
From voidflags.U:

This variable contains the default value of the "VOIDUSED" symbol (15).

direntrytype
From i_dirent.U:

This symbol is set to "struct direct" or "struct dirent" depending on whether dirent is available or not. You should use this pseudo type to portably declare your directory entries.

dlext
From dlext.U:

This variable contains the extension that is to be used for the dynamically loaded modules that perl generaties.

dlsrc
From dlsrc.U:

This variable contains the name of the dynamic loading file that will be used with the package.

doublesize
From doublesize.U:

This variable contains the value of the "DOUBLESIZE" symbol, which indicates to the C program how many bytes there are in a double.

drand01
From randfunc.U:

Indicates the macro to be used to generate normalized random numbers. Uses randfunc, often divided by (double) (((unsigned long) 1 << randbits)) in order to normalize the result. In C programs, the macro "Drand01" is mapped to drand01.

drand48_r_proto
From d_drand48_r.U:

This variable encodes the prototype of drand48_r. It is zero if d_drand48_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_drand48_r is defined.

dtrace
From usedtrace.U:

This variable holds the location of the dtrace executable.

dynamic_ext
From Extensions.U:

This variable holds a list of "XS" extension files we want to link dynamically into the package. It is used by Makefile.

e

eagain
From nblock_io.U:

This variable bears the symbolic errno code set by read() when no data is present on the file and non-blocking I/O was enabled (otherwise, read() blocks naturally).

ebcdic
From ebcdic.U:

This variable conditionally defines "EBCDIC" if this system uses "EBCDIC" encoding. Among other things, this means that the character ranges are not contiguous. See trnl.U

echo
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the echo program. After Configure runs, the value is reset to a plain "echo" and is not useful.

egrep
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the egrep program. After Configure runs, the value is reset to a plain "egrep" and is not useful.

emacs
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

endgrent_r_proto
From d_endgrent_r.U:

This variable encodes the prototype of endgrent_r. It is zero if d_endgrent_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_endgrent_r is defined.

endhostent_r_proto
From d_endhostent_r.U:

This variable encodes the prototype of endhostent_r. It is zero if d_endhostent_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_endhostent_r is defined.

endnetent_r_proto
From d_endnetent_r.U:

This variable encodes the prototype of endnetent_r. It is zero if d_endnetent_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_endnetent_r is defined.

endprotoent_r_proto
From d_endprotoent_r.U:

This variable encodes the prototype of endprotoent_r. It is zero if d_endprotoent_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_endprotoent_r is defined.

endpwent_r_proto
From d_endpwent_r.U:

This variable encodes the prototype of endpwent_r. It is zero if d_endpwent_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_endpwent_r is defined.

endservent_r_proto
From d_endservent_r.U:

This variable encodes the prototype of endservent_r. It is zero if d_endservent_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_endservent_r is defined.

eunicefix
From Init.U:

When running under Eunice this variable contains a command which will convert a shell script to the proper form of text file for it to be executable by the shell. On other systems it is a no-op.

exe_ext
From Unix.U:

This is an old synonym for _exe.

expr
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the expr program. After Configure runs, the value is reset to a plain "expr" and is not useful.

extensions
From Extensions.U:

This variable holds a list of all extension files (both "XS" and non-xs linked into the package. It is propagated to Config.pm and is typically used to test whether a particular extesion is available.

extern_C
From Csym.U:

"ANSI" C requires "extern" where C++ requires 'extern "C"'. This variable can be used in Configure to do the right thing.

extras
From Extras.U:

This variable holds a list of extra modules to install.

f

fflushall
From fflushall.U:

This symbol, if defined, tells that to flush all pending stdio output one must loop through all the stdio file handles stored in an array and fflush them. Note that if fflushNULL is defined, fflushall will not even be probed for and will be left undefined.

fflushNULL
From fflushall.U:

This symbol, if defined, tells that fflush("NULL") does flush all pending stdio output.

find
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

firstmakefile
From Unix.U:

This variable defines the first file searched by make. On unix, it is makefile (then Makefile). On case-insensitive systems, it might be something else. This is only used to deal with convoluted make depend tricks.

flex
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

fpossize
From fpossize.U:

This variable contains the size of a fpostype in bytes.

fpostype
From fpostype.U:

This variable defines Fpos_t to be something like fpos_t, long, uint, or whatever type is used to declare file positions in libc.

freetype
From mallocsrc.U:

This variable contains the return type of free(). It is usually void, but occasionally int.

from
From Cross.U:

This variable contains the command used by Configure to copy files from the target host. Useful and available only during Perl build. The string ":" if not cross-compiling.

full_ar
From Loc_ar.U:

This variable contains the full pathname to "ar", whether or not the user has specified "portability". This is only used in the Makefile.SH.

full_csh
From d_csh.U:

This variable contains the full pathname to "csh", whether or not the user has specified "portability". This is only used in the compiled C program, and we assume that all systems which can share this executable will have the same full pathname to csh.

full_sed
From Loc_sed.U:

This variable contains the full pathname to "sed", whether or not the user has specified "portability". This is only used in the compiled C program, and we assume that all systems which can share this executable will have the same full pathname to sed.

g

gccansipedantic
From gccvers.U:

If "GNU" cc (gcc) is used, this variable will enable (if set) the -ansi and -pedantic ccflags for building core files (through cflags script). (See Porting/pumpkin.pod for full description).

gccosandvers
From gccvers.U:

If "GNU" cc (gcc) is used, this variable holds the operating system and version used to compile gcc. It is set to '' if not gcc, or if nothing useful can be parsed as the os version.

gccversion
From gccvers.U:

If "GNU" cc (gcc) is used, this variable holds 1 or 2 to indicate whether the compiler is version 1 or 2. This is used in setting some of the default cflags. It is set to '' if not gcc.

getgrent_r_proto
From d_getgrent_r.U:

This variable encodes the prototype of getgrent_r. It is zero if d_getgrent_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_getgrent_r is defined.

getgrgid_r_proto
From d_getgrgid_r.U:

This variable encodes the prototype of getgrgid_r. It is zero if d_getgrgid_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_getgrgid_r is defined.

getgrnam_r_proto
From d_getgrnam_r.U:

This variable encodes the prototype of getgrnam_r. It is zero if d_getgrnam_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_getgrnam_r is defined.

gethostbyaddr_r_proto
From d_gethostbyaddr_r.U:

This variable encodes the prototype of gethostbyaddr_r. It is zero if d_gethostbyaddr_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_gethostbyaddr_r is defined.

gethostbyname_r_proto
From d_gethostbyname_r.U:

This variable encodes the prototype of gethostbyname_r. It is zero if d_gethostbyname_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_gethostbyname_r is defined.

gethostent_r_proto
From d_gethostent_r.U:

This variable encodes the prototype of gethostent_r. It is zero if d_gethostent_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_gethostent_r is defined.

getlogin_r_proto
From d_getlogin_r.U:

This variable encodes the prototype of getlogin_r. It is zero if d_getlogin_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_getlogin_r is defined.

getnetbyaddr_r_proto
From d_getnetbyaddr_r.U:

This variable encodes the prototype of getnetbyaddr_r. It is zero if d_getnetbyaddr_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_getnetbyaddr_r is defined.

getnetbyname_r_proto
From d_getnetbyname_r.U:

This variable encodes the prototype of getnetbyname_r. It is zero if d_getnetbyname_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_getnetbyname_r is defined.

getnetent_r_proto
From d_getnetent_r.U:

This variable encodes the prototype of getnetent_r. It is zero if d_getnetent_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_getnetent_r is defined.

getprotobyname_r_proto
From d_getprotobyname_r.U:

This variable encodes the prototype of getprotobyname_r. It is zero if d_getprotobyname_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_getprotobyname_r is defined.

getprotobynumber_r_proto
From d_getprotobynumber_r.U:

This variable encodes the prototype of getprotobynumber_r. It is zero if d_getprotobynumber_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_getprotobynumber_r is defined.

getprotoent_r_proto
From d_getprotoent_r.U:

This variable encodes the prototype of getprotoent_r. It is zero if d_getprotoent_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_getprotoent_r is defined.

getpwent_r_proto
From d_getpwent_r.U:

This variable encodes the prototype of getpwent_r. It is zero if d_getpwent_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_getpwent_r is defined.

getpwnam_r_proto
From d_getpwnam_r.U:

This variable encodes the prototype of getpwnam_r. It is zero if d_getpwnam_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_getpwnam_r is defined.

getpwuid_r_proto
From d_getpwuid_r.U:

This variable encodes the prototype of getpwuid_r. It is zero if d_getpwuid_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_getpwuid_r is defined.

getservbyname_r_proto
From d_getservbyname_r.U:

This variable encodes the prototype of getservbyname_r. It is zero if d_getservbyname_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_getservbyname_r is defined.

getservbyport_r_proto
From d_getservbyport_r.U:

This variable encodes the prototype of getservbyport_r. It is zero if d_getservbyport_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_getservbyport_r is defined.

getservent_r_proto
From d_getservent_r.U:

This variable encodes the prototype of getservent_r. It is zero if d_getservent_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_getservent_r is defined.

getspnam_r_proto
From d_getspnam_r.U:

This variable encodes the prototype of getspnam_r. It is zero if d_getspnam_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_getspnam_r is defined.

gidformat
From gidf.U:

This variable contains the format string used for printing a Gid_t.

gidsign
From gidsign.U:

This variable contains the signedness of a gidtype. 1 for unsigned, -1 for signed.

gidsize
From gidsize.U:

This variable contains the size of a gidtype in bytes.

gidtype
From gidtype.U:

This variable defines Gid_t to be something like gid_t, int, ushort, or whatever type is used to declare the return type of getgid(). Typically, it is the type of group ids in the kernel.

glibpth
From libpth.U:

This variable holds the general path (space-separated) used to find libraries. It may contain directories that do not exist on this platform, libpth is the cleaned-up version.

gmake
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the gmake program. After Configure runs, the value is reset to a plain "gmake" and is not useful.

gmtime_r_proto
From d_gmtime_r.U:

This variable encodes the prototype of gmtime_r. It is zero if d_gmtime_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_gmtime_r is defined.

gnulibc_version
From d_gnulibc.U:

This variable contains the version number of the "GNU" C library. It is usually something like 2.2.5. It is a plain '' if this is not the "GNU" C library, or if the version is unknown.

grep
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the grep program. After Configure runs, the value is reset to a plain "grep" and is not useful.

groupcat
From nis.U:

This variable contains a command that produces the text of the /etc/group file. This is normally "cat /etc/group``, but can be ''ypcat group" when "NIS" is used. On some systems, such as os390, there may be no equivalent command, in which case this variable is unset.

groupstype
From groupstype.U:

This variable defines Groups_t to be something like gid_t, int, ushort, or whatever type is used for the second argument to getgroups() and setgroups(). Usually, this is the same as gidtype (gid_t), but sometimes it isn't.

gzip
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the gzip program. After Configure runs, the value is reset to a plain "gzip" and is not useful.

h

h_fcntl
From h_fcntl.U:

This is variable gets set in various places to tell i_fcntl that <fcntl.h> should be included.

h_sysfile
From h_sysfile.U:

This is variable gets set in various places to tell i_sys_file that <sys/file.h> should be included.

hint
From Oldconfig.U:

Gives the type of hints used for previous answers. May be one of "default", "recommended" or "previous".

hostcat
From nis.U:

This variable contains a command that produces the text of the /etc/hosts file. This is normally "cat /etc/hosts``, but can be ''ypcat hosts" when "NIS" is used. On some systems, such as os390, there may be no equivalent command, in which case this variable is unset.

html1dir
From html1dir.U:

This variable contains the name of the directory in which html source pages are to be put. This directory is for pages that describe whole programs, not libraries or modules. It is intended to correspond roughly to section 1 of the Unix manuals.

html1direxp
From html1dir.U:

This variable is the same as the html1dir variable, but is filename expanded at configuration time, for convenient use in makefiles.

html3dir
From html3dir.U:

This variable contains the name of the directory in which html source pages are to be put. This directory is for pages that describe libraries or modules. It is intended to correspond roughly to section 3 of the Unix manuals.

html3direxp
From html3dir.U:

This variable is the same as the html3dir variable, but is filename expanded at configuration time, for convenient use in makefiles.

i

i16size
From perlxv.U:

This variable is the size of an I16 in bytes.

i16type
From perlxv.U:

This variable contains the C type used for Perl's I16.

i32size
From perlxv.U:

This variable is the size of an I32 in bytes.

i32type
From perlxv.U:

This variable contains the C type used for Perl's I32.

i64size
From perlxv.U:

This variable is the size of an I64 in bytes.

i64type
From perlxv.U:

This variable contains the C type used for Perl's I64.

i8size
From perlxv.U:

This variable is the size of an I8 in bytes.

i8type
From perlxv.U:

This variable contains the C type used for Perl's I8.

i_arpainet
From i_arpainet.U:

This variable conditionally defines the "I_ARPA_INET" symbol, and indicates whether a C program should include <arpa/inet.h>.

i_assert
From i_assert.U:

This variable conditionally defines the "I_ASSERT" symbol, which indicates to the C program that <assert.h> exists and could be included.

i_bsdioctl
From i_sysioctl.U:

This variable conditionally defines the "I_SYS_BSDIOCTL" symbol, which indicates to the C program that <sys/bsdioctl.h> exists and should be included.

i_crypt
From i_crypt.U:

This variable conditionally defines the "I_CRYPT" symbol, and indicates whether a C program should include <crypt.h>.

i_db
From i_db.U:

This variable conditionally defines the "I_DB" symbol, and indicates whether a C program may include Berkeley's "DB" include file <db.h>.

i_dbm
From i_dbm.U:

This variable conditionally defines the "I_DBM" symbol, which indicates to the C program that <dbm.h> exists and should be included.

i_dirent
From i_dirent.U:

This variable conditionally defines "I_DIRENT", which indicates to the C program that it should include <dirent.h>.

i_dld
From i_dld.U:

This variable conditionally defines the "I_DLD" symbol, which indicates to the C program that <dld.h> ("GNU" dynamic loading) exists and should be included.

i_dlfcn
From i_dlfcn.U:

This variable conditionally defines the "I_DLFCN" symbol, which indicates to the C program that <dlfcn.h> exists and should be included.

i_fcntl
From i_fcntl.U:

This variable controls the value of "I_FCNTL" (which tells the C program to include <fcntl.h>).

i_float
From i_float.U:

This variable conditionally defines the "I_FLOAT" symbol, and indicates whether a C program may include <float.h> to get symbols like "DBL_MAX" or "DBL_MIN", i.e. machine dependent floating point values.

i_fp
From i_fp.U:

This variable conditionally defines the "I_FP" symbol, and indicates whether a C program should include <fp.h>.

i_fp_class
From i_fp_class.U:

This variable conditionally defines the "I_FP_CLASS" symbol, and indicates whether a C program should include <fp_class.h>.

i_gdbm
From i_gdbm.U:

This variable conditionally defines the "I_GDBM" symbol, which indicates to the C program that <gdbm.h> exists and should be included.

i_gdbm_ndbm
From i_ndbm.U:

This variable conditionally defines the "I_GDBM_NDBM" symbol, which indicates to the C program that <gdbm-ndbm.h> exists and should be included. This is the location of the ndbm.h compatibility file in Debian 4.0.

i_gdbmndbm
From i_ndbm.U:

This variable conditionally defines the "I_GDBMNDBM" symbol, which indicates to the C program that <gdbm/ndbm.h> exists and should be included. This was the location of the ndbm.h compatibility file in RedHat 7.1.

i_grp
From i_grp.U:

This variable conditionally defines the "I_GRP" symbol, and indicates whether a C program should include <grp.h>.

i_ieeefp
From i_ieeefp.U:

This variable conditionally defines the "I_IEEEFP" symbol, and indicates whether a C program should include <ieeefp.h>.

i_inttypes
From i_inttypes.U:

This variable conditionally defines the "I_INTTYPES" symbol, and indicates whether a C program should include <inttypes.h>.

i_langinfo
From i_langinfo.U:

This variable conditionally defines the "I_LANGINFO" symbol, and indicates whether a C program should include <langinfo.h>.

i_libutil
From i_libutil.U:

This variable conditionally defines the "I_LIBUTIL" symbol, and indicates whether a C program should include <libutil.h>.

i_limits
From i_limits.U:

This variable conditionally defines the "I_LIMITS" symbol, and indicates whether a C program may include <limits.h> to get symbols like "WORD_BIT" and friends.

i_locale
From i_locale.U:

This variable conditionally defines the "I_LOCALE" symbol, and indicates whether a C program should include <locale.h>.

i_machcthr
From i_machcthr.U:

This variable conditionally defines the "I_MACH_CTHREADS" symbol, and indicates whether a C program should include <mach/cthreads.h>.

i_malloc
From i_malloc.U:

This variable conditionally defines the "I_MALLOC" symbol, and indicates whether a C program should include <malloc.h>.

i_mallocmalloc
From i_mallocmalloc.U:

This variable conditionally defines the "I_MALLOCMALLOC" symbol, and indicates whether a C program should include <malloc/malloc.h>.

i_math
From i_math.U:

This variable conditionally defines the "I_MATH" symbol, and indicates whether a C program may include <math.h>.

i_memory
From i_memory.U:

This variable conditionally defines the "I_MEMORY" symbol, and indicates whether a C program should include <memory.h>.

i_mntent
From i_mntent.U:

This variable conditionally defines the "I_MNTENT" symbol, and indicates whether a C program should include <mntent.h>.

i_ndbm
From i_ndbm.U:

This variable conditionally defines the "I_NDBM" symbol, which indicates to the C program that <ndbm.h> exists and should be included.

i_netdb
From i_netdb.U:

This variable conditionally defines the "I_NETDB" symbol, and indicates whether a C program should include <netdb.h>.

i_neterrno
From i_neterrno.U:

This variable conditionally defines the "I_NET_ERRNO" symbol, which indicates to the C program that <net/errno.h> exists and should be included.

i_netinettcp
From i_netinettcp.U:

This variable conditionally defines the "I_NETINET_TCP" symbol, and indicates whether a C program should include <netinet/tcp.h>.

i_niin
From i_niin.U:

This variable conditionally defines "I_NETINET_IN", which indicates to the C program that it should include <netinet/in.h>. Otherwise, you may try <sys/in.h>.

i_poll
From i_poll.U:

This variable conditionally defines the "I_POLL" symbol, and indicates whether a C program should include <poll.h>.

i_prot
From i_prot.U:

This variable conditionally defines the "I_PROT" symbol, and indicates whether a C program should include <prot.h>.

i_pthread
From i_pthread.U:

This variable conditionally defines the "I_PTHREAD" symbol, and indicates whether a C program should include <pthread.h>.

i_pwd
From i_pwd.U:

This variable conditionally defines "I_PWD", which indicates to the C program that it should include <pwd.h>.

i_rpcsvcdbm
From i_dbm.U:

This variable conditionally defines the "I_RPCSVC_DBM" symbol, which indicates to the C program that <rpcsvc/dbm.h> exists and should be included. Some System V systems might need this instead of <dbm.h>.

i_sfio
From i_sfio.U:

This variable conditionally defines the "I_SFIO" symbol, and indicates whether a C program should include <sfio.h>.

i_sgtty
From i_termio.U:

This variable conditionally defines the "I_SGTTY" symbol, which indicates to the C program that it should include <sgtty.h> rather than <termio.h>.

i_shadow
From i_shadow.U:

This variable conditionally defines the "I_SHADOW" symbol, and indicates whether a C program should include <shadow.h>.

i_socks
From i_socks.U:

This variable conditionally defines the "I_SOCKS" symbol, and indicates whether a C program should include <socks.h>.

i_stdarg
From i_varhdr.U:

This variable conditionally defines the "I_STDARG" symbol, which indicates to the C program that <stdarg.h> exists and should be included.

i_stddef
From i_stddef.U:

This variable conditionally defines the "I_STDDEF" symbol, which indicates to the C program that <stddef.h> exists and should be included.

i_stdlib
From i_stdlib.U:

This variable conditionally defines the "I_STDLIB" symbol, which indicates to the C program that <stdlib.h> exists and should be included.

i_string
From i_string.U:

This variable conditionally defines the "I_STRING" symbol, which indicates that <string.h> should be included rather than <strings.h>.

i_sunmath
From i_sunmath.U:

This variable conditionally defines the "I_SUNMATH" symbol, and indicates whether a C program should include <sunmath.h>.

i_sysaccess
From i_sysaccess.U:

This variable conditionally defines the "I_SYS_ACCESS" symbol, and indicates whether a C program should include <sys/access.h>.

i_sysdir
From i_sysdir.U:

This variable conditionally defines the "I_SYS_DIR" symbol, and indicates whether a C program should include <sys/dir.h>.

i_sysfile
From i_sysfile.U:

This variable conditionally defines the "I_SYS_FILE" symbol, and indicates whether a C program should include <sys/file.h> to get "R_OK" and friends.

i_sysfilio
From i_sysioctl.U:

This variable conditionally defines the "I_SYS_FILIO" symbol, which indicates to the C program that <sys/filio.h> exists and should be included in preference to <sys/ioctl.h>.

i_sysin
From i_niin.U:

This variable conditionally defines "I_SYS_IN", which indicates to the C program that it should include <sys/in.h> instead of <netinet/in.h>.

i_sysioctl
From i_sysioctl.U:

This variable conditionally defines the "I_SYS_IOCTL" symbol, which indicates to the C program that <sys/ioctl.h> exists and should be included.

i_syslog
From i_syslog.U:

This variable conditionally defines the "I_SYSLOG" symbol, and indicates whether a C program should include <syslog.h>.

i_sysmman
From i_sysmman.U:

This variable conditionally defines the "I_SYS_MMAN" symbol, and indicates whether a C program should include <sys/mman.h>.

i_sysmode
From i_sysmode.U:

This variable conditionally defines the "I_SYSMODE" symbol, and indicates whether a C program should include <sys/mode.h>.

i_sysmount
From i_sysmount.U:

This variable conditionally defines the "I_SYSMOUNT" symbol, and indicates whether a C program should include <sys/mount.h>.

i_sysndir
From i_sysndir.U:

This variable conditionally defines the "I_SYS_NDIR" symbol, and indicates whether a C program should include <sys/ndir.h>.

i_sysparam
From i_sysparam.U:

This variable conditionally defines the "I_SYS_PARAM" symbol, and indicates whether a C program should include <sys/param.h>.

i_syspoll
From i_syspoll.U:

This variable conditionally defines the "I_SYS_POLL" symbol, which indicates to the C program that it should include <sys/poll.h>.

i_sysresrc
From i_sysresrc.U:

This variable conditionally defines the "I_SYS_RESOURCE" symbol, and indicates whether a C program should include <sys/resource.h>.

i_syssecrt
From i_syssecrt.U:

This variable conditionally defines the "I_SYS_SECURITY" symbol, and indicates whether a C program should include <sys/security.h>.

i_sysselct
From i_sysselct.U:

This variable conditionally defines "I_SYS_SELECT", which indicates to the C program that it should include <sys/select.h> in order to get the definition of struct timeval.

i_syssockio
From i_sysioctl.U:

This variable conditionally defines "I_SYS_SOCKIO" to indicate to the C program that socket ioctl codes may be found in <sys/sockio.h> instead of <sys/ioctl.h>.

i_sysstat
From i_sysstat.U:

This variable conditionally defines the "I_SYS_STAT" symbol, and indicates whether a C program should include <sys/stat.h>.

i_sysstatfs
From i_sysstatfs.U:

This variable conditionally defines the "I_SYSSTATFS" symbol, and indicates whether a C program should include <sys/statfs.h>.

i_sysstatvfs
From i_sysstatvfs.U:

This variable conditionally defines the "I_SYSSTATVFS" symbol, and indicates whether a C program should include <sys/statvfs.h>.

i_systime
From i_time.U:

This variable conditionally defines "I_SYS_TIME", which indicates to the C program that it should include <sys/time.h>.

i_systimek
From i_time.U:

This variable conditionally defines "I_SYS_TIME_KERNEL", which indicates to the C program that it should include <sys/time.h> with "KERNEL" defined.

i_systimes
From i_systimes.U:

This variable conditionally defines the "I_SYS_TIMES" symbol, and indicates whether a C program should include <sys/times.h>.

i_systypes
From i_systypes.U:

This variable conditionally defines the "I_SYS_TYPES" symbol, and indicates whether a C program should include <sys/types.h>.

i_sysuio
From i_sysuio.U:

This variable conditionally defines the "I_SYSUIO" symbol, and indicates whether a C program should include <sys/uio.h>.

i_sysun
From i_sysun.U:

This variable conditionally defines "I_SYS_UN", which indicates to the C program that it should include <sys/un.h> to get "UNIX" domain socket definitions.

i_sysutsname
From i_sysutsname.U:

This variable conditionally defines the "I_SYSUTSNAME" symbol, and indicates whether a C program should include <sys/utsname.h>.

i_sysvfs
From i_sysvfs.U:

This variable conditionally defines the "I_SYSVFS" symbol, and indicates whether a C program should include <sys/vfs.h>.

i_syswait
From i_syswait.U:

This variable conditionally defines "I_SYS_WAIT", which indicates to the C program that it should include <sys/wait.h>.

i_termio
From i_termio.U:

This variable conditionally defines the "I_TERMIO" symbol, which indicates to the C program that it should include <termio.h> rather than <sgtty.h>.

i_termios
From i_termio.U:

This variable conditionally defines the "I_TERMIOS" symbol, which indicates to the C program that the "POSIX" <termios.h> file is to be included.

i_time
From i_time.U:

This variable conditionally defines "I_TIME", which indicates to the C program that it should include <time.h>.

i_unistd
From i_unistd.U:

This variable conditionally defines the "I_UNISTD" symbol, and indicates whether a C program should include <unistd.h>.

i_ustat
From i_ustat.U:

This variable conditionally defines the "I_USTAT" symbol, and indicates whether a C program should include <ustat.h>.

i_utime
From i_utime.U:

This variable conditionally defines the "I_UTIME" symbol, and indicates whether a C program should include <utime.h>.

i_values
From i_values.U:

This variable conditionally defines the "I_VALUES" symbol, and indicates whether a C program may include <values.h> to get symbols like "MAXLONG" and friends.

i_varargs
From i_varhdr.U:

This variable conditionally defines "I_VARARGS", which indicates to the C program that it should include <varargs.h>.

i_varhdr
From i_varhdr.U:

Contains the name of the header to be included to get va_dcl definition. Typically one of varargs.h or stdarg.h.

i_vfork
From i_vfork.U:

This variable conditionally defines the "I_VFORK" symbol, and indicates whether a C program should include vfork.h.

ignore_versioned_solibs
From libs.U:

This variable should be non-empty if non-versioned shared libraries (libfoo.so.x.y) are to be ignored (because they cannot be linked against).

inc_version_list
From inc_version_list.U:

This variable specifies the list of subdirectories in over which perl.c:incpush() and lib/lib.pm will automatically search when adding directories to @"INC". The elements in the list are separated by spaces. This is only useful if you have a perl library directory tree structured like the default one. See "INSTALL" for how this works. The versioned site_perl directory was introduced in 5.005, so that is the lowest possible value.

This list includes architecture-dependent directories back to version $api_versionstring (e.g. 5.5.640) and architecture-independent directories all the way back to 5.005.

inc_version_list_init
From inc_version_list.U:

This variable holds the same list as inc_version_list, but each item is enclosed in double quotes and separated by commas, suitable for use in the "PERL_INC_VERSION_LIST" initialization.

incpath
From usrinc.U:

This variable must preceed the normal include path to get hte right one, as in $incpath/usr/include or $incpath/usr/lib. Value can be "" or /bsd43 on mips.

inews
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

initialinstalllocation
From bin.U:

When userelocatableinc is true, this variable holds the location that make install should copy the perl binary to, with all the run-time relocatable paths calculated from this at install time. When used, it is initialised to the original value of binexp, and then binexp is set to .../, as the other binaries are found relative to the perl binary.

installarchlib
From archlib.U:

This variable is really the same as archlibexp but may differ on those systems using "AFS". For extra portability, only this variable should be used in makefiles.

installbin
From bin.U:

This variable is the same as binexp unless "AFS" is running in which case the user is explicitely prompted for it. This variable should always be used in your makefiles for maximum portability.

installhtml1dir
From html1dir.U:

This variable is really the same as html1direxp, unless you are using a different installprefix. For extra portability, you should only use this variable within your makefiles.

installhtml3dir
From html3dir.U:

This variable is really the same as html3direxp, unless you are using a different installprefix. For extra portability, you should only use this variable within your makefiles.

installman1dir
From man1dir.U:

This variable is really the same as man1direxp, unless you are using "AFS" in which case it points to the read/write location whereas man1direxp only points to the read-only access location. For extra portability, you should only use this variable within your makefiles.

installman3dir
From man3dir.U:

This variable is really the same as man3direxp, unless you are using "AFS" in which case it points to the read/write location whereas man3direxp only points to the read-only access location. For extra portability, you should only use this variable within your makefiles.

installprefix
From installprefix.U:

This variable holds the name of the directory below which ``make install'' will install the package. For most users, this is the same as prefix. However, it is useful for installing the software into a different (usually temporary) location after which it can be bundled up and moved somehow to the final location specified by prefix.

installprefixexp
From installprefix.U:

This variable holds the full absolute path of installprefix with all ~-expansion done.

installprivlib
From privlib.U:

This variable is really the same as privlibexp but may differ on those systems using "AFS". For extra portability, only this variable should be used in makefiles.

installscript
From scriptdir.U:

This variable is usually the same as scriptdirexp, unless you are on a system running "AFS", in which case they may differ slightly. You should always use this variable within your makefiles for portability.

installsitearch
From sitearch.U:

This variable is really the same as sitearchexp but may differ on those systems using "AFS". For extra portability, only this variable should be used in makefiles.

installsitebin
From sitebin.U:

This variable is usually the same as sitebinexp, unless you are on a system running "AFS", in which case they may differ slightly. You should always use this variable within your makefiles for portability.

installsitehtml1dir
From sitehtml1dir.U:

This variable is really the same as sitehtml1direxp, unless you are using "AFS" in which case it points to the read/write location whereas html1direxp only points to the read-only access location. For extra portability, you should only use this variable within your makefiles.

installsitehtml3dir
From sitehtml3dir.U:

This variable is really the same as sitehtml3direxp, unless you are using "AFS" in which case it points to the read/write location whereas html3direxp only points to the read-only access location. For extra portability, you should only use this variable within your makefiles.

installsitelib
From sitelib.U:

This variable is really the same as sitelibexp but may differ on those systems using "AFS". For extra portability, only this variable should be used in makefiles.

installsiteman1dir
From siteman1dir.U:

This variable is really the same as siteman1direxp, unless you are using "AFS" in which case it points to the read/write location whereas man1direxp only points to the read-only access location. For extra portability, you should only use this variable within your makefiles.

installsiteman3dir
From siteman3dir.U:

This variable is really the same as siteman3direxp, unless you are using "AFS" in which case it points to the read/write location whereas man3direxp only points to the read-only access location. For extra portability, you should only use this variable within your makefiles.

installsitescript
From sitescript.U:

This variable is usually the same as sitescriptexp, unless you are on a system running "AFS", in which case they may differ slightly. You should always use this variable within your makefiles for portability.

installstyle
From installstyle.U:

This variable describes the "style" of the perl installation. This is intended to be useful for tools that need to manipulate entire perl distributions. Perl itself doesn't use this to find its libraries --- the library directories are stored directly in Config.pm. Currently, there are only two styles: "lib" and lib/perl5. The default library locations (e.g. privlib, sitelib) are either $prefix/lib or $prefix/lib/perl5. The former is useful if $prefix is a directory dedicated to perl (e.g. /opt/perl), while the latter is useful if $prefix is shared by many packages, e.g. if $prefix=/usr/local.

Unfortunately, while this "style" variable is used to set defaults for all three directory hierarchies (core, vendor, and site), there is no guarantee that the same style is actually appropriate for all those directories. For example, $prefix might be /opt/perl, but $siteprefix might be /usr/local. (Perhaps, in retrospect, the "lib" style should never have been supported, but it did seem like a nice idea at the time.)

The situation is even less clear for tools such as MakeMaker that can be used to install additional modules into non-standard places. For example, if a user intends to install a module into a private directory (perhaps by setting "PREFIX" on the Makefile.PL command line), then there is no reason to assume that the Configure-time $installstyle setting will be relevant for that "PREFIX".

This may later be extended to include other information, so be careful with pattern-matching on the results.

For compatibility with perl5.005 and earlier, the default setting is based on whether or not $prefix contains the string "perl".

installusrbinperl
From instubperl.U:

This variable tells whether Perl should be installed also as /usr/bin/perl in addition to $installbin/perl

installvendorarch
From vendorarch.U:

This variable is really the same as vendorarchexp but may differ on those systems using "AFS". For extra portability, only this variable should be used in makefiles.

installvendorbin
From vendorbin.U:

This variable is really the same as vendorbinexp but may differ on those systems using "AFS". For extra portability, only this variable should be used in makefiles.

installvendorhtml1dir
From vendorhtml1dir.U:

This variable is really the same as vendorhtml1direxp but may differ on those systems using "AFS". For extra portability, only this variable should be used in makefiles.

installvendorhtml3dir
From vendorhtml3dir.U:

This variable is really the same as vendorhtml3direxp but may differ on those systems using "AFS". For extra portability, only this variable should be used in makefiles.

installvendorlib
From vendorlib.U:

This variable is really the same as vendorlibexp but may differ on those systems using "AFS". For extra portability, only this variable should be used in makefiles.

installvendorman1dir
From vendorman1dir.U:

This variable is really the same as vendorman1direxp but may differ on those systems using "AFS". For extra portability, only this variable should be used in makefiles.

installvendorman3dir
From vendorman3dir.U:

This variable is really the same as vendorman3direxp but may differ on those systems using "AFS". For extra portability, only this variable should be used in makefiles.

installvendorscript
From vendorscript.U:

This variable is really the same as vendorscriptexp but may differ on those systems using "AFS". For extra portability, only this variable should be used in makefiles.

intsize
From intsize.U:

This variable contains the value of the "INTSIZE" symbol, which indicates to the C program how many bytes there are in an int.

issymlink
From issymlink.U:

This variable holds the test command to test for a symbolic link (if they are supported). Typical values include "test -h" and "test -L".

ivdformat
From perlxvf.U:

This variable contains the format string used for printing a Perl "IV" as a signed decimal integer.

ivsize
From perlxv.U:

This variable is the size of an "IV" in bytes.

ivtype
From perlxv.U:

This variable contains the C type used for Perl's "IV".

k

known_extensions
From Extensions.U:

This variable holds a list of all "XS" extensions included in the package.

ksh
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

l

ld
From dlsrc.U:

This variable indicates the program to be used to link libraries for dynamic loading. On some systems, it is "ld". On "ELF" systems, it should be $cc. Mostly, we'll try to respect the hint file setting.

lddlflags
From dlsrc.U:

This variable contains any special flags that might need to be passed to $ld to create a shared library suitable for dynamic loading. It is up to the makefile to use it. For hpux, it should be "-b". For sunos 4.1, it is empty.

ldflags
From ccflags.U:

This variable contains any additional C loader flags desired by the user. It is up to the Makefile to use this.

ldflags_uselargefiles
From uselfs.U:

This variable contains the loader flags needed by large file builds and added to ldflags by hints files.

ldlibpthname
From libperl.U:

This variable holds the name of the shared library search path, often "LD_LIBRARY_PATH". To get an empty string, the hints file must set this to "none".

less
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the less program. After Configure runs, the value is reset to a plain "less" and is not useful.

lib_ext
From Unix.U:

This is an old synonym for _a.

libc
From libc.U:

This variable contains the location of the C library.

libperl
From libperl.U:

The perl executable is obtained by linking perlmain.c with libperl, any static extensions (usually just DynaLoader), and any other libraries needed on this system. libperl is usually libperl.a, but can also be libperl.so.xxx if the user wishes to build a perl executable with a shared library.

libpth
From libpth.U:

This variable holds the general path (space-separated) used to find libraries. It is intended to be used by other units.

libs
From libs.U:

This variable holds the additional libraries we want to use. It is up to the Makefile to deal with it. The list can be empty.

libsdirs
From libs.U:

This variable holds the directory names aka dirnames of the libraries we found and accepted, duplicates are removed.

libsfiles
From libs.U:

This variable holds the filenames aka basenames of the libraries we found and accepted.

libsfound
From libs.U:

This variable holds the full pathnames of the libraries we found and accepted.

libspath
From libs.U:

This variable holds the directory names probed for libraries.

libswanted
From Myinit.U:

This variable holds a list of all the libraries we want to search. The order is chosen to pick up the c library ahead of ucb or bsd libraries for SVR4.

libswanted_uselargefiles
From uselfs.U:

This variable contains the libraries needed by large file builds and added to ldflags by hints files. It is a space separated list of the library names without the "lib" prefix or any suffix, just like libswanted..

line
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

lint
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

lkflags
From ccflags.U:

This variable contains any additional C partial linker flags desired by the user. It is up to the Makefile to use this.

ln
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the ln program. After Configure runs, the value is reset to a plain "ln" and is not useful.

lns
From lns.U:

This variable holds the name of the command to make symbolic links (if they are supported). It can be used in the Makefile. It is either "ln -s" or "ln"

localtime_r_proto
From d_localtime_r.U:

This variable encodes the prototype of localtime_r. It is zero if d_localtime_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_localtime_r is defined.

locincpth
From ccflags.U:

This variable contains a list of additional directories to be searched by the compiler. The appropriate "-I" directives will be added to ccflags. This is intended to simplify setting local directories from the Configure command line. It's not much, but it parallels the loclibpth stuff in libpth.U.

loclibpth
From libpth.U:

This variable holds the paths (space-separated) used to find local libraries. It is prepended to libpth, and is intended to be easily set from the command line.

longdblsize
From d_longdbl.U:

This variable contains the value of the "LONG_DOUBLESIZE" symbol, which indicates to the C program how many bytes there are in a long double, if this system supports long doubles.

longlongsize
From d_longlong.U:

This variable contains the value of the "LONGLONGSIZE" symbol, which indicates to the C program how many bytes there are in a long long, if this system supports long long.

longsize
From intsize.U:

This variable contains the value of the "LONGSIZE" symbol, which indicates to the C program how many bytes there are in a long.

lp
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

lpr
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

ls
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the ls program. After Configure runs, the value is reset to a plain "ls" and is not useful.

lseeksize
From lseektype.U:

This variable defines lseektype to be something like off_t, long, or whatever type is used to declare lseek offset's type in the kernel (which also appears to be lseek's return type).

lseektype
From lseektype.U:

This variable defines lseektype to be something like off_t, long, or whatever type is used to declare lseek offset's type in the kernel (which also appears to be lseek's return type).

m

mad
From mad.U:

This variable indicates that the Misc Attribute Definition code is to be compiled.

madlyh
From mad.U:

If the Misc Attribute Decoration is to be compiled, this variable is set to the name of the extra header files to be used, else it is ''

madlyobj
From mad.U:

If the Misc Attribute Decoration is to be compiled, this variable is set to the name of the extra object files to be used, else it is ''

madlysrc
From mad.U:

If the Misc Attribute Decoration is to be compiled, this variable is set to the name of the extra C source files to be used, else it is ''

mail
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

mailx
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

make
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the make program. After Configure runs, the value is reset to a plain "make" and is not useful.

make_set_make
From make.U:

Some versions of "make" set the variable "MAKE". Others do not. This variable contains the string to be included in Makefile.SH so that "MAKE" is set if needed, and not if not needed. Possible values are:

make_set_make="#"            # If your make program handles this for you,

make_set_make="MAKE=$make"   # if it doesn't.

This uses a comment character so that we can distinguish a "set" value (from a previous config.sh or Configure "-D" option) from an uncomputed value.

mallocobj
From mallocsrc.U:

This variable contains the name of the malloc.o that this package generates, if that malloc.o is preferred over the system malloc. Otherwise the value is null. This variable is intended for generating Makefiles. See mallocsrc.

mallocsrc
From mallocsrc.U:

This variable contains the name of the malloc.c that comes with the package, if that malloc.c is preferred over the system malloc. Otherwise the value is null. This variable is intended for generating Makefiles.

malloctype
From mallocsrc.U:

This variable contains the kind of ptr returned by malloc and realloc.

man1dir
From man1dir.U:

This variable contains the name of the directory in which manual source pages are to be put. It is the responsibility of the Makefile.SH to get the value of this into the proper command. You must be prepared to do the ~name expansion yourself.

man1direxp
From man1dir.U:

This variable is the same as the man1dir variable, but is filename expanded at configuration time, for convenient use in makefiles.

man1ext
From man1dir.U:

This variable contains the extension that the manual page should have: one of "n", "l", or 1. The Makefile must supply the .. See man1dir.

man3dir
From man3dir.U:

This variable contains the name of the directory in which manual source pages are to be put. It is the responsibility of the Makefile.SH to get the value of this into the proper command. You must be prepared to do the ~name expansion yourself.

man3direxp
From man3dir.U:

This variable is the same as the man3dir variable, but is filename expanded at configuration time, for convenient use in makefiles.

man3ext
From man3dir.U:

This variable contains the extension that the manual page should have: one of "n", "l", or 3. The Makefile must supply the .. See man3dir.

mips_type
From usrinc.U:

This variable holds the environment type for the mips system. Possible values are ``BSD 4.3'' and ``System V''.

mistrustnm
From Csym.U:

This variable can be used to establish a fallthrough for the cases where nm fails to find a symbol. If usenm is false or usenm is true and mistrustnm is false, this variable has no effect. If usenm is true and mistrustnm is "compile", a test program will be compiled to try to find any symbol that can't be located via nm lookup. If mistrustnm is "run", the test program will be run as well as being compiled.

mkdir
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the mkdir program. After Configure runs, the value is reset to a plain "mkdir" and is not useful.

mmaptype
From d_mmap.U:

This symbol contains the type of pointer returned by mmap() (and simultaneously the type of the first argument). It can be "void *" or "caddr_t".

modetype
From modetype.U:

This variable defines modetype to be something like mode_t, int, unsigned short, or whatever type is used to declare file modes for system calls.

more
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the more program. After Configure runs, the value is reset to a plain "more" and is not useful.

multiarch
From multiarch.U:

This variable conditionally defines the "MULTIARCH" symbol which signifies the presence of multiplatform files. This is normally set by hints files.

mv
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

myarchname
From archname.U:

This variable holds the architecture name computed by Configure in a previous run. It is not intended to be perused by any user and should never be set in a hint file.

mydomain
From myhostname.U:

This variable contains the eventual value of the "MYDOMAIN" symbol, which is the domain of the host the program is going to run on. The domain must be appended to myhostname to form a complete host name. The dot comes with mydomain, and need not be supplied by the program.

myhostname
From myhostname.U:

This variable contains the eventual value of the "MYHOSTNAME" symbol, which is the name of the host the program is going to run on. The domain is not kept with hostname, but must be gotten from mydomain. The dot comes with mydomain, and need not be supplied by the program.

myuname
From Oldconfig.U:

The output of "uname -a" if available, otherwise the hostname. On Xenix, pseudo variables assignments in the output are stripped, thank you. The whole thing is then lower-cased.

n

n
From n.U:

This variable contains the "-n" flag if that is what causes the echo command to suppress newline. Otherwise it is null. Correct usage is $echo $n ``prompt for a question: $c''.

need_va_copy
From need_va_copy.U:

This symbol, if defined, indicates that the system stores the variable argument list datatype, va_list, in a format that cannot be copied by simple assignment, so that some other means must be used when copying is required. As such systems vary in their provision (or non-provision) of copying mechanisms, handy.h defines a platform- "independent" macro, Perl_va_copy(src, dst), to do the job.

netdb_hlen_type
From netdbtype.U:

This variable holds the type used for the 2nd argument to gethostbyaddr(). Usually, this is int or size_t or unsigned. This is only useful if you have gethostbyaddr(), naturally.

netdb_host_type
From netdbtype.U:

This variable holds the type used for the 1st argument to gethostbyaddr(). Usually, this is char * or void *, possibly with or without a const prefix. This is only useful if you have gethostbyaddr(), naturally.

netdb_name_type
From netdbtype.U:

This variable holds the type used for the argument to gethostbyname(). Usually, this is char * or const char *. This is only useful if you have gethostbyname(), naturally.

netdb_net_type
From netdbtype.U:

This variable holds the type used for the 1st argument to getnetbyaddr(). Usually, this is int or long. This is only useful if you have getnetbyaddr(), naturally.

nm
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the nm program. After Configure runs, the value is reset to a plain "nm" and is not useful.

nm_opt
From usenm.U:

This variable holds the options that may be necessary for nm.

nm_so_opt
From usenm.U:

This variable holds the options that may be necessary for nm to work on a shared library but that can not be used on an archive library. Currently, this is only used by Linux, where nm --dynamic is *required* to get symbols from an "ELF" library which has been stripped, but nm --dynamic is *fatal* on an archive library. Maybe Linux should just always set usenm=false.

nonxs_ext
From Extensions.U:

This variable holds a list of all non-xs extensions included in the package. All of them will be built.

nroff
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the nroff program. After Configure runs, the value is reset to a plain "nroff" and is not useful.

nv_overflows_integers_at
From perlxv.U:

This variable gives the largest integer value that NVs can hold as a constant floating point expression. If it could not be determined, it holds the value 0.

nv_preserves_uv_bits
From perlxv.U:

This variable indicates how many of bits type uvtype a variable nvtype can preserve.

nveformat
From perlxvf.U:

This variable contains the format string used for printing a Perl "NV" using %e-ish floating point format.

nvEUformat
From perlxvf.U:

This variable contains the format string used for printing a Perl "NV" using %E-ish floating point format.

nvfformat
From perlxvf.U:

This variable confains the format string used for printing a Perl "NV" using %f-ish floating point format.

nvFUformat
From perlxvf.U:

This variable confains the format string used for printing a Perl "NV" using %F-ish floating point format.

nvgformat
From perlxvf.U:

This variable contains the format string used for printing a Perl "NV" using %g-ish floating point format.

nvGUformat
From perlxvf.U:

This variable contains the format string used for printing a Perl "NV" using %G-ish floating point format.

nvsize
From perlxv.U:

This variable is the size of an "NV" in bytes.

nvtype
From perlxv.U:

This variable contains the C type used for Perl's "NV".

o

o_nonblock
From nblock_io.U:

This variable bears the symbol value to be used during open() or fcntl() to turn on non-blocking I/O for a file descriptor. If you wish to switch between blocking and non-blocking, you may try ioctl("FIOSNBIO") instead, but that is only supported by some devices.

obj_ext
From Unix.U:

This is an old synonym for _o.

old_pthread_create_joinable
From d_pthrattrj.U:

This variable defines the constant to use for creating joinable (aka undetached) pthreads. Unused if pthread.h defines "PTHREAD_CREATE_JOINABLE". If used, possible values are "PTHREAD_CREATE_UNDETACHED" and "__UNDETACHED".

optimize
From ccflags.U:

This variable contains any optimizer/debugger flag that should be used. It is up to the Makefile to use it.

orderlib
From orderlib.U:

This variable is "true" if the components of libraries must be ordered (with `lorder $* | tsort`) before placing them in an archive. Set to "false" if ranlib or ar can generate random libraries.

osname
From Oldconfig.U:

This variable contains the operating system name (e.g. sunos, solaris, hpux, etc.). It can be useful later on for setting defaults. Any spaces are replaced with underscores. It is set to a null string if we can't figure it out.

osvers
From Oldconfig.U:

This variable contains the operating system version (e.g. 4.1.3, 5.2, etc.). It is primarily used for helping select an appropriate hints file, but might be useful elsewhere for setting defaults. It is set to '' if we can't figure it out. We try to be flexible about how much of the version number to keep, e.g. if 4.1.1, 4.1.2, and 4.1.3 are essentially the same for this package, hints files might just be os_4.0 or os_4.1, etc., not keeping separate files for each little release.

otherlibdirs
From otherlibdirs.U:

This variable contains a colon-separated set of paths for the perl binary to search for additional library files or modules. These directories will be tacked to the end of @"INC". Perl will automatically search below each path for version- and architecture-specific directories. See inc_version_list for more details. A value of " " means "none" and is used to preserve this value for the next run through Configure.

p

package
From package.U:

This variable contains the name of the package being constructed. It is primarily intended for the use of later Configure units.

pager
From pager.U:

This variable contains the name of the preferred pager on the system. Usual values are (the full pathnames of) more, less, pg, or cat.

passcat
From nis.U:

This variable contains a command that produces the text of the /etc/passwd file. This is normally "cat /etc/passwd``, but can be ''ypcat passwd" when "NIS" is used. On some systems, such as os390, there may be no equivalent command, in which case this variable is unset.

patchlevel
From patchlevel.U:

The patchlevel level of this package. The value of patchlevel comes from the patchlevel.h file. In a version number such as 5.6.1, this is the 6. In patchlevel.h, this is referred to as "PERL_VERSION".

path_sep
From Unix.U:

This is an old synonym for p_ in Head.U, the character used to separate elements in the command shell search "PATH".

perl
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

perl5
From perl5.U:

This variable contains the full path (if any) to a previously installed perl5.005 or later suitable for running the script to determine inc_version_list.

P

PERL_API_REVISION
From patchlevel.h:

This number describes the earliest compatible "PERL_REVISION" of Perl ("compatibility" here being defined as sufficient binary/"API" compatibility to run "XS" code built with the older version). Normally this does not change across maintenance releases. Please read the comment in patchlevel.h.

PERL_API_SUBVERSION
From patchlevel.h:

This number describes the earliest compatible "PERL_SUBVERSION" of Perl ("compatibility" here being defined as sufficient binary/"API" compatibility to run "XS" code built with the older version). Normally this does not change across maintenance releases. Please read the comment in patchlevel.h.

PERL_API_VERSION
From patchlevel.h:

This number describes the earliest compatible "PERL_VERSION" of Perl ("compatibility" here being defined as sufficient binary/"API" compatibility to run "XS" code built with the older version). Normally this does not change across maintenance releases. Please read the comment in patchlevel.h.

PERL_CONFIG_SH
From Oldsyms.U:

This is set to "true" in config.sh so that a shell script sourcing config.sh can tell if it has been sourced already.

PERL_PATCHLEVEL
From Oldsyms.U:

This symbol reflects the patchlevel, if available. Will usually come from the .patch file, which is available when the perl source tree was fetched with rsync.

perl_patchlevel
From patchlevel.U:

This is the Perl patch level, a numeric change identifier, as defined by whichever source code maintenance system is used to maintain the patches; currently Perforce. It does not correlate with the Perl version numbers or the maintenance versus development dichotomy except by also being increasing.

PERL_REVISION
From Oldsyms.U:

In a Perl version number such as 5.6.2, this is the 5. This value is manually set in patchlevel.h

PERL_SUBVERSION
From Oldsyms.U:

In a Perl version number such as 5.6.2, this is the 2. Values greater than 50 represent potentially unstable development subversions. This value is manually set in patchlevel.h

PERL_VERSION
From Oldsyms.U:

In a Perl version number such as 5.6.2, this is the 6. This value is manually set in patchlevel.h

perladmin
From perladmin.U:

Electronic mail address of the perl5 administrator.

perllibs
From End.U:

The list of libraries needed by Perl only (any libraries needed by extensions only will by dropped, if using dynamic loading).

perlpath
From perlpath.U:

This variable contains the eventual value of the "PERLPATH" symbol, which contains the name of the perl interpreter to be used in shell scripts and in the "eval "exec"" idiom. This variable is not necessarily the pathname of the file containing the perl interpreter; you must append the executable extension (_exe) if it is not already present. Note that Perl code that runs during the Perl build process cannot reference this variable, as Perl may not have been installed, or even if installed, may be a different version of Perl.

pg
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the pg program. After Configure runs, the value is reset to a plain "pg" and is not useful.

phostname
From myhostname.U:

This variable contains the eventual value of the "PHOSTNAME" symbol, which is a command that can be fed to popen() to get the host name. The program should probably not presume that the domain is or isn't there already.

pidtype
From pidtype.U:

This variable defines "PIDTYPE" to be something like pid_t, int, ushort, or whatever type is used to declare process ids in the kernel.

plibpth
From libpth.U:

Holds the private path used by Configure to find out the libraries. Its value is prepend to libpth. This variable takes care of special machines, like the mips. Usually, it should be empty.

pmake
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

pr
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

prefix
From prefix.U:

This variable holds the name of the directory below which the user will install the package. Usually, this is /usr/local, and executables go in /usr/local/bin, library stuff in /usr/local/lib, man pages in /usr/local/man, etc. It is only used to set defaults for things in bin.U, mansrc.U, privlib.U, or scriptdir.U.

prefixexp
From prefix.U:

This variable holds the full absolute path of the directory below which the user will install the package. Derived from prefix.

privlib
From privlib.U:

This variable contains the eventual value of the "PRIVLIB" symbol, which is the name of the private library for this package. It may have a ~ on the front. It is up to the makefile to eventually create this directory while performing installation (with ~ substitution).

privlibexp
From privlib.U:

This variable is the ~name expanded version of privlib, so that you may use it directly in Makefiles or shell scripts.

procselfexe
From d_procselfexe.U:

If d_procselfexe is defined, $procselfexe is the filename of the symbolic link pointing to the absolute pathname of the executing program.

prototype
From prototype.U:

This variable holds the eventual value of "CAN_PROTOTYPE", which indicates the C compiler can handle funciton prototypes.

ptrsize
From ptrsize.U:

This variable contains the value of the "PTRSIZE" symbol, which indicates to the C program how many bytes there are in a pointer.

q

quadkind
From quadtype.U:

This variable, if defined, encodes the type of a quad: 1 = int, 2 = long, 3 = long long, 4 = int64_t.

quadtype
From quadtype.U:

This variable defines Quad_t to be something like long, int, long long, int64_t, or whatever type is used for 64-bit integers.

r

randbits
From randfunc.U:

Indicates how many bits are produced by the function used to generate normalized random numbers.

randfunc
From randfunc.U:

Indicates the name of the random number function to use. Values include drand48, random, and rand. In C programs, the "Drand01" macro is defined to generate uniformly distributed random numbers over the range [0., 1.[ (see drand01 and nrand).

random_r_proto
From d_random_r.U:

This variable encodes the prototype of random_r. It is zero if d_random_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_random_r is defined.

randseedtype
From randfunc.U:

Indicates the type of the argument of the seedfunc.

ranlib
From orderlib.U:

This variable is set to the pathname of the ranlib program, if it is needed to generate random libraries. Set to ":" if ar can generate random libraries or if random libraries are not supported

rd_nodata
From nblock_io.U:

This variable holds the return code from read() when no data is present. It should be -1, but some systems return 0 when "O_NDELAY" is used, which is a shame because you cannot make the difference between no data and an EOF.. Sigh!

readdir64_r_proto
From d_readdir64_r.U:

This variable encodes the prototype of readdir64_r. It is zero if d_readdir64_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_readdir64_r is defined.

readdir_r_proto
From d_readdir_r.U:

This variable encodes the prototype of readdir_r. It is zero if d_readdir_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_readdir_r is defined.

revision
From patchlevel.U:

The value of revision comes from the patchlevel.h file. In a version number such as 5.6.1, this is the 5. In patchlevel.h, this is referred to as "PERL_REVISION".

rm
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the rm program. After Configure runs, the value is reset to a plain "rm" and is not useful.

rm_try
From Unix.U:

This is a cleanup variable for try test programs. Internal Configure use only.

rmail
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

run
From Cross.U:

This variable contains the command used by Configure to copy and execute a cross-compiled executable in the target host. Useful and available only during Perl build. Empty string '' if not cross-compiling.

runnm
From usenm.U:

This variable contains "true" or "false" depending whether the nm extraction should be performed or not, according to the value of usenm and the flags on the Configure command line.

s

sched_yield
From d_pthread_y.U:

This variable defines the way to yield the execution of the current thread.

scriptdir
From scriptdir.U:

This variable holds the name of the directory in which the user wants to put publicly scripts for the package in question. It is either the same directory as for binaries, or a special one that can be mounted across different architectures, like /usr/share. Programs must be prepared to deal with ~name expansion.

scriptdirexp
From scriptdir.U:

This variable is the same as scriptdir, but is filename expanded at configuration time, for programs not wanting to bother with it.

sed
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the sed program. After Configure runs, the value is reset to a plain "sed" and is not useful.

seedfunc
From randfunc.U:

Indicates the random number generating seed function. Values include srand48, srandom, and srand.

selectminbits
From selectminbits.U:

This variable holds the minimum number of bits operated by select. That is, if you do select(n, ...), how many bits at least will be cleared in the masks if some activity is detected. Usually this is either n or 32*ceil(n/32), especially many little-endians do the latter. This is only useful if you have select(), naturally.

selecttype
From selecttype.U:

This variable holds the type used for the 2nd, 3rd, and 4th arguments to select. Usually, this is "fd_set *", if "HAS_FD_SET" is defined, and "int *" otherwise. This is only useful if you have select(), naturally.

sendmail
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

setgrent_r_proto
From d_setgrent_r.U:

This variable encodes the prototype of setgrent_r. It is zero if d_setgrent_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_setgrent_r is defined.

sethostent_r_proto
From d_sethostent_r.U:

This variable encodes the prototype of sethostent_r. It is zero if d_sethostent_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_sethostent_r is defined.

setlocale_r_proto
From d_setlocale_r.U:

This variable encodes the prototype of setlocale_r. It is zero if d_setlocale_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_setlocale_r is defined.

setnetent_r_proto
From d_setnetent_r.U:

This variable encodes the prototype of setnetent_r. It is zero if d_setnetent_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_setnetent_r is defined.

setprotoent_r_proto
From d_setprotoent_r.U:

This variable encodes the prototype of setprotoent_r. It is zero if d_setprotoent_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_setprotoent_r is defined.

setpwent_r_proto
From d_setpwent_r.U:

This variable encodes the prototype of setpwent_r. It is zero if d_setpwent_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_setpwent_r is defined.

setservent_r_proto
From d_setservent_r.U:

This variable encodes the prototype of setservent_r. It is zero if d_setservent_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_setservent_r is defined.

sGMTIME_max
From time_size.U:

This variable defines the maximum value of the time_t offset that the system function gmtime () accepts

sGMTIME_min
From time_size.U:

This variable defines the minimum value of the time_t offset that the system function gmtime () accepts

sh
From sh.U:

This variable contains the full pathname of the shell used on this system to execute Bourne shell scripts. Usually, this will be /bin/sh, though it's possible that some systems will have /bin/ksh, /bin/pdksh, /bin/ash, /bin/bash, or even something such as D:/bin/sh.exe. This unit comes before Options.U, so you can't set sh with a "-D" option, though you can override this (and startsh) with "-O -Dsh=/bin/whatever -Dstartsh=whatever"

shar
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

sharpbang
From spitshell.U:

This variable contains the string #! if this system supports that construct.

shmattype
From d_shmat.U:

This symbol contains the type of pointer returned by shmat(). It can be "void *" or "char *".

shortsize
From intsize.U:

This variable contains the value of the "SHORTSIZE" symbol which indicates to the C program how many bytes there are in a short.

shrpenv
From libperl.U:

If the user builds a shared libperl.so, then we need to tell the "perl" executable where it will be able to find the installed libperl.so. One way to do this on some systems is to set the environment variable "LD_RUN_PATH" to the directory that will be the final location of the shared libperl.so. The makefile can use this with something like $shrpenv $("CC") -o perl perlmain.o $libperl $libs Typical values are shrpenv="env "LD_RUN_PATH"=$archlibexp/"CORE"" or shrpenv='' See the main perl Makefile.SH for actual working usage. Alternatively, we might be able to use a command line option such as -R $archlibexp/"CORE" (Solaris) or -Wl,-rpath $archlibexp/"CORE" (Linux).

shsharp
From spitshell.U:

This variable tells further Configure units whether your sh can handle # comments.

sig_count
From sig_name.U:

This variable holds a number larger than the largest valid signal number. This is usually the same as the "NSIG" macro.

sig_name
From sig_name.U:

This variable holds the signal names, space separated. The leading "SIG" in signal name is removed. A "ZERO" is prepended to the list. This is currently not used, sig_name_init is used instead.

sig_name_init
From sig_name.U:

This variable holds the signal names, enclosed in double quotes and separated by commas, suitable for use in the "SIG_NAME" definition below. A "ZERO" is prepended to the list, and the list is terminated with a plain 0. The leading "SIG" in signal names is removed. See sig_num.

sig_num
From sig_name.U:

This variable holds the signal numbers, space separated. A "ZERO" is prepended to the list (corresponding to the fake "SIGZERO"). Those numbers correspond to the value of the signal listed in the same place within the sig_name list. This is currently not used, sig_num_init is used instead.

sig_num_init
From sig_name.U:

This variable holds the signal numbers, enclosed in double quotes and separated by commas, suitable for use in the "SIG_NUM" definition below. A "ZERO" is prepended to the list, and the list is terminated with a plain 0.

sig_size
From sig_name.U:

This variable contains the number of elements of the sig_name and sig_num arrays.

signal_t
From d_voidsig.U:

This variable holds the type of the signal handler (void or int).

sitearch
From sitearch.U:

This variable contains the eventual value of the "SITEARCH" symbol, which is the name of the private library for this package. It may have a ~ on the front. It is up to the makefile to eventually create this directory while performing installation (with ~ substitution). The standard distribution will put nothing in this directory. After perl has been installed, users may install their own local architecture-dependent modules in this directory with MakeMaker Makefile.PL or equivalent. See "INSTALL" for details.

sitearchexp
From sitearch.U:

This variable is the ~name expanded version of sitearch, so that you may use it directly in Makefiles or shell scripts.

sitebin
From sitebin.U:

This variable holds the name of the directory in which the user wants to put add-on publicly executable files for the package in question. It is most often a local directory such as /usr/local/bin. Programs using this variable must be prepared to deal with ~name substitution. The standard distribution will put nothing in this directory. After perl has been installed, users may install their own local executables in this directory with MakeMaker Makefile.PL or equivalent. See "INSTALL" for details.

sitebinexp
From sitebin.U:

This is the same as the sitebin variable, but is filename expanded at configuration time, for use in your makefiles.

sitehtml1dir
From sitehtml1dir.U:

This variable contains the name of the directory in which site-specific html source pages are to be put. It is the responsibility of the Makefile.SH to get the value of this into the proper command. You must be prepared to do the ~name expansion yourself. The standard distribution will put nothing in this directory. After perl has been installed, users may install their own local html pages in this directory with MakeMaker Makefile.PL or equivalent. See "INSTALL" for details.

sitehtml1direxp
From sitehtml1dir.U:

This variable is the same as the sitehtml1dir variable, but is filename expanded at configuration time, for convenient use in makefiles.

sitehtml3dir
From sitehtml3dir.U:

This variable contains the name of the directory in which site-specific library html source pages are to be put. It is the responsibility of the Makefile.SH to get the value of this into the proper command. You must be prepared to do the ~name expansion yourself. The standard distribution will put nothing in this directory. After perl has been installed, users may install their own local library html pages in this directory with MakeMaker Makefile.PL or equivalent. See "INSTALL" for details.

sitehtml3direxp
From sitehtml3dir.U:

This variable is the same as the sitehtml3dir variable, but is filename expanded at configuration time, for convenient use in makefiles.

sitelib
From sitelib.U:

This variable contains the eventual value of the "SITELIB" symbol, which is the name of the private library for this package. It may have a ~ on the front. It is up to the makefile to eventually create this directory while performing installation (with ~ substitution). The standard distribution will put nothing in this directory. After perl has been installed, users may install their own local architecture-independent modules in this directory with MakeMaker Makefile.PL or equivalent. See "INSTALL" for details.

sitelib_stem
From sitelib.U:

This variable is $sitelibexp with any trailing version-specific component removed. The elements in inc_version_list (inc_version_list.U) can be tacked onto this variable to generate a list of directories to search.

sitelibexp
From sitelib.U:

This variable is the ~name expanded version of sitelib, so that you may use it directly in Makefiles or shell scripts.

siteman1dir
From siteman1dir.U:

This variable contains the name of the directory in which site-specific manual source pages are to be put. It is the responsibility of the Makefile.SH to get the value of this into the proper command. You must be prepared to do the ~name expansion yourself. The standard distribution will put nothing in this directory. After perl has been installed, users may install their own local man1 pages in this directory with MakeMaker Makefile.PL or equivalent. See "INSTALL" for details.

siteman1direxp
From siteman1dir.U:

This variable is the same as the siteman1dir variable, but is filename expanded at configuration time, for convenient use in makefiles.

siteman3dir
From siteman3dir.U:

This variable contains the name of the directory in which site-specific library man source pages are to be put. It is the responsibility of the Makefile.SH to get the value of this into the proper command. You must be prepared to do the ~name expansion yourself. The standard distribution will put nothing in this directory. After perl has been installed, users may install their own local man3 pages in this directory with MakeMaker Makefile.PL or equivalent. See "INSTALL" for details.

siteman3direxp
From siteman3dir.U:

This variable is the same as the siteman3dir variable, but is filename expanded at configuration time, for convenient use in makefiles.

siteprefix
From siteprefix.U:

This variable holds the full absolute path of the directory below which the user will install add-on packages. See "INSTALL" for usage and examples.

siteprefixexp
From siteprefix.U:

This variable holds the full absolute path of the directory below which the user will install add-on packages. Derived from siteprefix.

sitescript
From sitescript.U:

This variable holds the name of the directory in which the user wants to put add-on publicly executable files for the package in question. It is most often a local directory such as /usr/local/bin. Programs using this variable must be prepared to deal with ~name substitution. The standard distribution will put nothing in this directory. After perl has been installed, users may install their own local scripts in this directory with MakeMaker Makefile.PL or equivalent. See "INSTALL" for details.

sitescriptexp
From sitescript.U:

This is the same as the sitescript variable, but is filename expanded at configuration time, for use in your makefiles.

sizesize
From sizesize.U:

This variable contains the size of a sizetype in bytes.

sizetype
From sizetype.U:

This variable defines sizetype to be something like size_t, unsigned long, or whatever type is used to declare length parameters for string functions.

sleep
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

sLOCALTIME_max
From time_size.U:

This variable defines the maximum value of the time_t offset that the system function localtime () accepts

sLOCALTIME_min
From time_size.U:

This variable defines the minimum value of the time_t offset that the system function localtime () accepts

smail
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

so
From so.U:

This variable holds the extension used to identify shared libraries (also known as shared objects) on the system. Usually set to "so".

sockethdr
From d_socket.U:

This variable has any cpp "-I" flags needed for socket support.

socketlib
From d_socket.U:

This variable has the names of any libraries needed for socket support.

socksizetype
From socksizetype.U:

This variable holds the type used for the size argument for various socket calls like accept. Usual values include socklen_t, size_t, and int.

sort
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the sort program. After Configure runs, the value is reset to a plain "sort" and is not useful.

spackage
From package.U:

This variable contains the name of the package being constructed, with the first letter uppercased, i.e. suitable for starting sentences.

spitshell
From spitshell.U:

This variable contains the command necessary to spit out a runnable shell on this system. It is either cat or a grep "-v" for # comments.

sPRId64
From quadfio.U:

This variable, if defined, contains the string used by stdio to format 64-bit decimal numbers (format "d") for output.

sPRIeldbl
From longdblfio.U:

This variable, if defined, contains the string used by stdio to format long doubles (format "e") for output.

sPRIEUldbl
From longdblfio.U:

This variable, if defined, contains the string used by stdio to format long doubles (format "E") for output. The "U" in the name is to separate this from sPRIeldbl so that even case-blind systems can see the difference.

sPRIfldbl
From longdblfio.U:

This variable, if defined, contains the string used by stdio to format long doubles (format "f") for output.

sPRIFUldbl
From longdblfio.U:

This variable, if defined, contains the string used by stdio to format long doubles (format "F") for output. The "U" in the name is to separate this from sPRIfldbl so that even case-blind systems can see the difference.

sPRIgldbl
From longdblfio.U:

This variable, if defined, contains the string used by stdio to format long doubles (format "g") for output.

sPRIGUldbl
From longdblfio.U:

This variable, if defined, contains the string used by stdio to format long doubles (format "G") for output. The "U" in the name is to separate this from sPRIgldbl so that even case-blind systems can see the difference.

sPRIi64
From quadfio.U:

This variable, if defined, contains the string used by stdio to format 64-bit decimal numbers (format "i") for output.

sPRIo64
From quadfio.U:

This variable, if defined, contains the string used by stdio to format 64-bit octal numbers (format "o") for output.

sPRIu64
From quadfio.U:

This variable, if defined, contains the string used by stdio to format 64-bit unsigned decimal numbers (format "u") for output.

sPRIx64
From quadfio.U:

This variable, if defined, contains the string used by stdio to format 64-bit hexadecimal numbers (format "x") for output.

sPRIXU64
From quadfio.U:

This variable, if defined, contains the string used by stdio to format 64-bit hExADECimAl numbers (format "X") for output. The "U" in the name is to separate this from sPRIx64 so that even case-blind systems can see the difference.

srand48_r_proto
From d_srand48_r.U:

This variable encodes the prototype of srand48_r. It is zero if d_srand48_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_srand48_r is defined.

srandom_r_proto
From d_srandom_r.U:

This variable encodes the prototype of srandom_r. It is zero if d_srandom_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_srandom_r is defined.

src
From src.U:

This variable holds the (possibly relative) path of the package source. It is up to the Makefile to use this variable and set "VPATH" accordingly to find the sources remotely. Use $pkgsrc to have an absolute path.

sSCNfldbl
From longdblfio.U:

This variable, if defined, contains the string used by stdio to format long doubles (format "f") for input.

ssizetype
From ssizetype.U:

This variable defines ssizetype to be something like ssize_t, long or int. It is used by functions that return a count of bytes or an error condition. It must be a signed type. We will pick a type such that sizeof(SSize_t) == sizeof(Size_t).

startperl
From startperl.U:

This variable contains the string to put on the front of a perl script to make sure (hopefully) that it runs with perl and not some shell. Of course, that leading line must be followed by the classical perl idiom: eval 'exec perl -S $0 ${1+$@}' if $running_under_some_shell; to guarantee perl startup should the shell execute the script. Note that this magic incatation is not understood by csh.

startsh
From startsh.U:

This variable contains the string to put on the front of a shell script to make sure (hopefully) that it runs with sh and not some other shell.

static_ext
From Extensions.U:

This variable holds a list of "XS" extension files we want to link statically into the package. It is used by Makefile.

stdchar
From stdchar.U:

This variable conditionally defines "STDCHAR" to be the type of char used in stdio.h. It has the values ``unsigned char'' or "char".

stdio_base
From d_stdstdio.U:

This variable defines how, given a "FILE" pointer, fp, to access the _base field (or equivalent) of stdio.h's "FILE" structure. This will be used to define the macro FILE_base(fp).

stdio_bufsiz
From d_stdstdio.U:

This variable defines how, given a "FILE" pointer, fp, to determine the number of bytes store in the I/O buffer pointer to by the _base field (or equivalent) of stdio.h's "FILE" structure. This will be used to define the macro FILE_bufsiz(fp).

stdio_cnt
From d_stdstdio.U:

This variable defines how, given a "FILE" pointer, fp, to access the _cnt field (or equivalent) of stdio.h's "FILE" structure. This will be used to define the macro FILE_cnt(fp).

stdio_filbuf
From d_stdstdio.U:

This variable defines how, given a "FILE" pointer, fp, to tell stdio to refill its internal buffers (?). This will be used to define the macro FILE_filbuf(fp).

stdio_ptr
From d_stdstdio.U:

This variable defines how, given a "FILE" pointer, fp, to access the _ptr field (or equivalent) of stdio.h's "FILE" structure. This will be used to define the macro FILE_ptr(fp).

stdio_stream_array
From stdio_streams.U:

This variable tells the name of the array holding the stdio streams. Usual values include _iob, __iob, and __sF.

strerror_r_proto
From d_strerror_r.U:

This variable encodes the prototype of strerror_r. It is zero if d_strerror_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_strerror_r is defined.

strings
From i_string.U:

This variable holds the full path of the string header that will be used. Typically /usr/include/string.h or /usr/include/strings.h.

submit
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

subversion
From patchlevel.U:

The subversion level of this package. The value of subversion comes from the patchlevel.h file. In a version number such as 5.6.1, this is the 1. In patchlevel.h, this is referred to as "PERL_SUBVERSION". This is unique to perl.

sysman
From sysman.U:

This variable holds the place where the manual is located on this system. It is not the place where the user wants to put his manual pages. Rather it is the place where Configure may look to find manual for unix commands (section 1 of the manual usually). See mansrc.

t

tail
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

tar
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

targetarch
From Cross.U:

If cross-compiling, this variable contains the target architecture. If not, this will be empty.

tbl
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

tee
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

test
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the test program. After Configure runs, the value is reset to a plain "test" and is not useful.

timeincl
From i_time.U:

This variable holds the full path of the included time header(s).

timetype
From d_time.U:

This variable holds the type returned by time(). It can be long, or time_t on "BSD" sites (in which case <sys/types.h> should be included). Anyway, the type Time_t should be used.

tmpnam_r_proto
From d_tmpnam_r.U:

This variable encodes the prototype of tmpnam_r. It is zero if d_tmpnam_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_tmpnam_r is defined.

to
From Cross.U:

This variable contains the command used by Configure to copy to from the target host. Useful and available only during Perl build. The string ":" if not cross-compiling.

touch
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the touch program. After Configure runs, the value is reset to a plain "touch" and is not useful.

tr
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the tr program. After Configure runs, the value is reset to a plain "tr" and is not useful.

trnl
From trnl.U:

This variable contains the value to be passed to the tr(1) command to transliterate a newline. Typical values are "\012" and "\n". This is needed for "EBCDIC" systems where newline is not necessarily "\012".

troff
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

ttyname_r_proto
From d_ttyname_r.U:

This variable encodes the prototype of ttyname_r. It is zero if d_ttyname_r is undef, and one of the "REENTRANT_PROTO_T_ABC" macros of reentr.h if d_ttyname_r is defined.

u

u16size
From perlxv.U:

This variable is the size of an U16 in bytes.

u16type
From perlxv.U:

This variable contains the C type used for Perl's U16.

u32size
From perlxv.U:

This variable is the size of an U32 in bytes.

u32type
From perlxv.U:

This variable contains the C type used for Perl's U32.

u64size
From perlxv.U:

This variable is the size of an U64 in bytes.

u64type
From perlxv.U:

This variable contains the C type used for Perl's U64.

u8size
From perlxv.U:

This variable is the size of an U8 in bytes.

u8type
From perlxv.U:

This variable contains the C type used for Perl's U8.

uidformat
From uidf.U:

This variable contains the format string used for printing a Uid_t.

uidsign
From uidsign.U:

This variable contains the signedness of a uidtype. 1 for unsigned, -1 for signed.

uidsize
From uidsize.U:

This variable contains the size of a uidtype in bytes.

uidtype
From uidtype.U:

This variable defines Uid_t to be something like uid_t, int, ushort, or whatever type is used to declare user ids in the kernel.

uname
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the uname program. After Configure runs, the value is reset to a plain "uname" and is not useful.

uniq
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the uniq program. After Configure runs, the value is reset to a plain "uniq" and is not useful.

uquadtype
From quadtype.U:

This variable defines Uquad_t to be something like unsigned long, unsigned int, unsigned long long, uint64_t, or whatever type is used for 64-bit integers.

use5005threads
From usethreads.U:

This variable conditionally defines the USE_5005THREADS symbol, and indicates that Perl should be built to use the 5.005-based threading implementation. Only valid up to 5.8.x.

use64bitall
From use64bits.U:

This variable conditionally defines the USE_64_BIT_ALL symbol, and indicates that 64-bit integer types should be used when available. The maximal possible 64-bitness is employed: LP64 or ILP64, meaning that you will be able to use more than 2 gigabytes of memory. This mode is even more binary incompatible than USE_64_BIT_INT. You may not be able to run the resulting executable in a 32-bit "CPU" at all or you may need at least to reboot your "OS" to 64-bit mode.

use64bitint
From use64bits.U:

This variable conditionally defines the USE_64_BIT_INT symbol, and indicates that 64-bit integer types should be used when available. The minimal possible 64-bitness is employed, just enough to get 64-bit integers into Perl. This may mean using for example ``long longs'', while your memory may still be limited to 2 gigabytes.

usecrosscompile
From Cross.U:

This variable conditionally defines the "USE_CROSS_COMPILE" symbol, and indicates that Perl has been cross-compiled.

usedevel
From Devel.U:

This variable indicates that Perl was configured with development features enabled. This should not be done for production builds.

usedl
From dlsrc.U:

This variable indicates if the system supports dynamic loading of some sort. See also dlsrc and dlobj.

usedtrace
From usedtrace.U:

This variable indicates whether we are compiling with dtrace support. See also dtrace.

usefaststdio
From usefaststdio.U:

This variable conditionally defines the "USE_FAST_STDIO" symbol, and indicates that Perl should be built to use "fast stdio". Defaults to define in Perls 5.8 and earlier, to undef later.

useithreads
From usethreads.U:

This variable conditionally defines the "USE_ITHREADS" symbol, and indicates that Perl should be built to use the interpreter-based threading implementation.

uselargefiles
From uselfs.U:

This variable conditionally defines the "USE_LARGE_FILES" symbol, and indicates that large file interfaces should be used when available.

uselongdouble
From uselongdbl.U:

This variable conditionally defines the "USE_LONG_DOUBLE" symbol, and indicates that long doubles should be used when available.

usemallocwrap
From mallocsrc.U:

This variable contains y if we are wrapping malloc to prevent integer overflow during size calculations.

usemorebits
From usemorebits.U:

This variable conditionally defines the "USE_MORE_BITS" symbol, and indicates that explicit 64-bit interfaces and long doubles should be used when available.

usemultiplicity
From usemultiplicity.U:

This variable conditionally defines the "MULTIPLICITY" symbol, and indicates that Perl should be built to use multiplicity.

usemymalloc
From mallocsrc.U:

This variable contains y if the malloc that comes with this package is desired over the system's version of malloc. People often include special versions of malloc for effiency, but such versions are often less portable. See also mallocsrc and mallocobj. If this is "y", then -lmalloc is removed from $libs.

usenm
From usenm.U:

This variable contains "true" or "false" depending whether the nm extraction is wanted or not.

useopcode
From Extensions.U:

This variable holds either "true" or "false" to indicate whether the Opcode extension should be used. The sole use for this currently is to allow an easy mechanism for users to skip the Opcode extension from the Configure command line.

useperlio
From useperlio.U:

This variable conditionally defines the "USE_PERLIO" symbol, and indicates that the PerlIO abstraction should be used throughout.

useposix
From Extensions.U:

This variable holds either "true" or "false" to indicate whether the "POSIX" extension should be used. The sole use for this currently is to allow an easy mechanism for hints files to indicate that "POSIX" will not compile on a particular system.

usereentrant
From usethreads.U:

This variable conditionally defines the "USE_REENTRANT_API" symbol, which indicates that the thread code may try to use the various _r versions of library functions. This is only potentially meaningful if usethreads is set and is very experimental, it is not even prompted for.

userelocatableinc
From bin.U:

This variable is set to true to indicate that perl should relocate @"INC" entries at runtime based on the path to the perl binary. Any @"INC" paths starting .../ are relocated relative to the directory containing the perl binary, and a logical cleanup of the path is then made around the join point (removing dir/../ pairs)

usesfio
From d_sfio.U:

This variable is set to true when the user agrees to use sfio. It is set to false when sfio is not available or when the user explicitely requests not to use sfio. It is here primarily so that command-line settings can override the auto-detection of d_sfio without running into a ``WHOA THERE''.

useshrplib
From libperl.U:

This variable is set to "true" if the user wishes to build a shared libperl, and "false" otherwise.

usesitecustomize
From d_sitecustomize.U:

This variable is set to true when the user requires a mechanism that allows the sysadmin to add entries to @"INC" at runtime. This variable being set, makes perl run $sitelib/sitecustomize.pl at startup.

usesocks
From usesocks.U:

This variable conditionally defines the "USE_SOCKS" symbol, and indicates that Perl should be built to use "SOCKS".

usethreads
From usethreads.U:

This variable conditionally defines the "USE_THREADS" symbol, and indicates that Perl should be built to use threads.

usevendorprefix
From vendorprefix.U:

This variable tells whether the vendorprefix and consequently other vendor* paths are in use.

usevfork
From d_vfork.U:

This variable is set to true when the user accepts to use vfork. It is set to false when no vfork is available or when the user explicitely requests not to use vfork.

usrinc
From usrinc.U:

This variable holds the path of the include files, which is usually /usr/include. It is mainly used by other Configure units.

uuname
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

uvoformat
From perlxvf.U:

This variable contains the format string used for printing a Perl "UV" as an unsigned octal integer.

uvsize
From perlxv.U:

This variable is the size of a "UV" in bytes.

uvtype
From perlxv.U:

This variable contains the C type used for Perl's "UV".

uvuformat
From perlxvf.U:

This variable contains the format string used for printing a Perl "UV" as an unsigned decimal integer.

uvxformat
From perlxvf.U:

This variable contains the format string used for printing a Perl "UV" as an unsigned hexadecimal integer in lowercase abcdef.

uvXUformat
From perlxvf.U:

This variable contains the format string used for printing a Perl "UV" as an unsigned hexadecimal integer in uppercase "ABCDEF".

v

vaproto
From vaproto.U:

This variable conditionally defines "CAN_VAPROTO" on systems supporting prototype declaration of functions with a variable number of arguments. See also prototype.

vendorarch
From vendorarch.U:

This variable contains the value of the "PERL_VENDORARCH" symbol. It may have a ~ on the front. The standard distribution will put nothing in this directory. Vendors who distribute perl may wish to place their own architecture-dependent modules and extensions in this directory with MakeMaker Makefile.PL "INSTALLDIRS"=vendor or equivalent. See "INSTALL" for details.

vendorarchexp
From vendorarch.U:

This variable is the ~name expanded version of vendorarch, so that you may use it directly in Makefiles or shell scripts.

vendorbin
From vendorbin.U:

This variable contains the eventual value of the "VENDORBIN" symbol. It may have a ~ on the front. The standard distribution will put nothing in this directory. Vendors who distribute perl may wish to place additional binaries in this directory with MakeMaker Makefile.PL "INSTALLDIRS"=vendor or equivalent. See "INSTALL" for details.

vendorbinexp
From vendorbin.U:

This variable is the ~name expanded version of vendorbin, so that you may use it directly in Makefiles or shell scripts.

vendorhtml1dir
From vendorhtml1dir.U:

This variable contains the name of the directory for html pages. It may have a ~ on the front. The standard distribution will put nothing in this directory. Vendors who distribute perl may wish to place their own html pages in this directory with MakeMaker Makefile.PL "INSTALLDIRS"=vendor or equivalent. See "INSTALL" for details.

vendorhtml1direxp
From vendorhtml1dir.U:

This variable is the ~name expanded version of vendorhtml1dir, so that you may use it directly in Makefiles or shell scripts.

vendorhtml3dir
From vendorhtml3dir.U:

This variable contains the name of the directory for html library pages. It may have a ~ on the front. The standard distribution will put nothing in this directory. Vendors who distribute perl may wish to place their own html pages for modules and extensions in this directory with MakeMaker Makefile.PL "INSTALLDIRS"=vendor or equivalent. See "INSTALL" for details.

vendorhtml3direxp
From vendorhtml3dir.U:

This variable is the ~name expanded version of vendorhtml3dir, so that you may use it directly in Makefiles or shell scripts.

vendorlib
From vendorlib.U:

This variable contains the eventual value of the "VENDORLIB" symbol, which is the name of the private library for this package. The standard distribution will put nothing in this directory. Vendors who distribute perl may wish to place their own modules in this directory with MakeMaker Makefile.PL "INSTALLDIRS"=vendor or equivalent. See "INSTALL" for details.

vendorlib_stem
From vendorlib.U:

This variable is $vendorlibexp with any trailing version-specific component removed. The elements in inc_version_list (inc_version_list.U) can be tacked onto this variable to generate a list of directories to search.

vendorlibexp
From vendorlib.U:

This variable is the ~name expanded version of vendorlib, so that you may use it directly in Makefiles or shell scripts.

vendorman1dir
From vendorman1dir.U:

This variable contains the name of the directory for man1 pages. It may have a ~ on the front. The standard distribution will put nothing in this directory. Vendors who distribute perl may wish to place their own man1 pages in this directory with MakeMaker Makefile.PL "INSTALLDIRS"=vendor or equivalent. See "INSTALL" for details.

vendorman1direxp
From vendorman1dir.U:

This variable is the ~name expanded version of vendorman1dir, so that you may use it directly in Makefiles or shell scripts.

vendorman3dir
From vendorman3dir.U:

This variable contains the name of the directory for man3 pages. It may have a ~ on the front. The standard distribution will put nothing in this directory. Vendors who distribute perl may wish to place their own man3 pages in this directory with MakeMaker Makefile.PL "INSTALLDIRS"=vendor or equivalent. See "INSTALL" for details.

vendorman3direxp
From vendorman3dir.U:

This variable is the ~name expanded version of vendorman3dir, so that you may use it directly in Makefiles or shell scripts.

vendorprefix
From vendorprefix.U:

This variable holds the full absolute path of the directory below which the vendor will install add-on packages. See "INSTALL" for usage and examples.

vendorprefixexp
From vendorprefix.U:

This variable holds the full absolute path of the directory below which the vendor will install add-on packages. Derived from vendorprefix.

vendorscript
From vendorscript.U:

This variable contains the eventual value of the "VENDORSCRIPT" symbol. It may have a ~ on the front. The standard distribution will put nothing in this directory. Vendors who distribute perl may wish to place additional executable scripts in this directory with MakeMaker Makefile.PL "INSTALLDIRS"=vendor or equivalent. See "INSTALL" for details.

vendorscriptexp
From vendorscript.U:

This variable is the ~name expanded version of vendorscript, so that you may use it directly in Makefiles or shell scripts.

version
From patchlevel.U:

The full version number of this package, such as 5.6.1 (or 5_6_1). This combines revision, patchlevel, and subversion to get the full version number, including any possible subversions. This is suitable for use as a directory name, and hence is filesystem dependent.

version_patchlevel_string
From patchlevel.U:

This is a string combining version, subversion and perl_patchlevel (if perl_patchlevel is non-zero). It is typically something like 'version 7 subversion 1' or 'version 7 subversion 1 patchlevel 11224' It is computed here to avoid duplication of code in myconfig.SH and lib/Config.pm.

versiononly
From versiononly.U:

If set, this symbol indicates that only the version-specific components of a perl installation should be installed. This may be useful for making a test installation of a new version without disturbing the existing installation. Setting versiononly is equivalent to setting installperl's -v option. In particular, the non-versioned scripts and programs such as a2p, c2ph, h2xs, pod2*, and perldoc are not installed (see "INSTALL" for a more complete list). Nor are the man pages installed. Usually, this is undef.

vi
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

voidflags
From voidflags.U:

This variable contains the eventual value of the "VOIDFLAGS" symbol, which indicates how much support of the void type is given by this compiler. See "VOIDFLAGS" for more info.

x

xlibpth
From libpth.U:

This variable holds extra path (space-separated) used to find libraries on this platform, for example "CPU"-specific libraries (on multi-"CPU" platforms) may be listed here.

y

yacc
From yacc.U:

This variable holds the name of the compiler compiler we want to use in the Makefile. It can be yacc, byacc, or bison -y.

yaccflags
From yacc.U:

This variable contains any additional yacc flags desired by the user. It is up to the Makefile to use this.

z

zcat
From Loc.U:

This variable is defined but not used by Configure. The value is the empty string and is not useful.

zip
From Loc.U:

This variable is used internally by Configure to determine the full pathname (if any) of the zip program. After Configure runs, the value is reset to a plain "zip" and is not useful.

GIT DATA

Information on the git commit from which the current perl binary was compiled can be found in the variable $Config::Git_Data. The variable is a structured string that looks something like this:
   git_commit_id='ea0c2dbd5f5ac6845ecc7ec6696415bf8e27bd52'
   git_describe='GitLive-blead-1076-gea0c2db'
   git_branch='smartmatch'
   git_uncommitted_changes=''
   git_commit_id_title='Commit id:'
   git_commit_date='2009-05-09 17:47:31 +0200'
 
 

Its format is not guaranteed not to change over time.

NOTE

This module contains a good example of how to use tie to implement a cache and an example of how to make a tied variable readonly to those outside of it.