Linux Certif

Toute la documentation sur la certification Linux LPI

__gnu_cxx::stdio_filebuf

NAME

__gnu_cxx::stdio_filebuf - Provides a layer of compatibility for C/POSIX.

SYNOPSIS

Inherits basic_filebuf< _CharT, _Traits >.

Public Types

typedef codecvt< char_type, char, __state_type > __codecvt_type

typedef __basic_file< char > __file_type

typedef basic_filebuf< char_type, traits_type > __filebuf_type

typedef traits_type::state_type __state_type

typedef basic_streambuf< char_type, traits_type > __streambuf_type

typedef _CharT char_type

typedef traits_type::int_type int_type

typedef traits_type::off_type off_type

typedef traits_type::pos_type pos_type

typedef std::size_t size_t

typedef _Traits traits_type

Public Member Functions

__filebuf_type * close () throw ()

int fd ()

std::__c_file * file ()

streamsize in_avail ()

bool is_open () const throw ()

__filebuf_type * open (const char *__s, ios_base::openmode __mode)

int_type sbumpc ()

int_type sgetc ()

streamsize sgetn (char_type *__s, streamsize __n)

int_type snextc ()

int_type sputbackc (char_type __c)

int_type sputc (char_type __c)

streamsize sputn (const char_type *__s, streamsize __n)

stdio_filebuf (std::__c_file *__f, std::ios_base::openmode __mode, size_t __size=static_cast< size_t >(BUFSIZ))

stdio_filebuf (int __fd, std::ios_base::openmode __mode, size_t __size=static_cast< size_t >(BUFSIZ))

stdio_filebuf ()

void stossc ()

int_type sungetc ()

virtual ~stdio_filebuf ()

Protected Member Functions

void _M_allocate_internal_buffer ()

bool _M_convert_to_external (char_type *, streamsize)

void _M_create_pback ()

void _M_destroy_internal_buffer () throw ()

void _M_destroy_pback () throw ()

pos_type _M_seek (off_type __off, ios_base::seekdir __way, __state_type __state)

void _M_set_buffer (streamsize __off)

bool _M_terminate_output ()

void gbump (int __n)

virtual void imbue (const locale &__loc)

virtual int_type overflow (int_type __c=_Traits::eof())

virtual int_type pbackfail (int_type __c=_Traits::eof())

void pbump (int __n)

virtual pos_type seekoff (off_type __off, ios_base::seekdir __way, ios_base::openmode __mode=ios_base::in|ios_base::out)

virtual pos_type seekpos (pos_type __pos, ios_base::openmode __mode=ios_base::in|ios_base::out)

virtual __streambuf_type * setbuf (char_type *__s, streamsize __n)

void setg (char_type *__gbeg, char_type *__gnext, char_type *__gend)

void setp (char_type *__pbeg, char_type *__pend)

virtual streamsize showmanyc ()

virtual int sync ()

virtual int_type uflow ()

virtual int_type underflow ()

virtual streamsize xsgetn (char_type *__s, streamsize __n)

virtual streamsize xsputn (const char_type *__s, streamsize __n)

char_type * eback () const

char_type * egptr () const

char_type * gptr () const

char_type * epptr () const

char_type * pbase () const

char_type * pptr () const

Protected Attributes

char_type * _M_buf

bool _M_buf_allocated

size_t _M_buf_size

const __codecvt_type * _M_codecvt

char * _M_ext_buf

streamsize _M_ext_buf_size

char * _M_ext_end

const char * _M_ext_next

__file_type _M_file

__c_lock _M_lock

ios_base::openmode _M_mode

bool _M_reading

__state_type _M_state_beg

__state_type _M_state_cur

__state_type _M_state_last

bool _M_writing

char_type _M_pback

char_type * _M_pback_cur_save

char_type * _M_pback_end_save

bool _M_pback_init

Friends

__gnu_cxx::__enable_if< __is_char< _CharT2 >::__value, _CharT2 * >::__type __copy_aux (istreambuf_iterator< _CharT2 >, istreambuf_iterator< _CharT2 >, _CharT2 *)

streamsize __copy_streambufs_eof (__streambuf_type *, __streambuf_type *, bool &)

class basic_ios< char_type, traits_type >

class basic_istream< char_type, traits_type >

class basic_ostream< char_type, traits_type >

__gnu_cxx::__enable_if< __is_char< _CharT2 >::__value, istreambuf_iterator< _CharT2 > >::__type find (istreambuf_iterator< _CharT2 >, istreambuf_iterator< _CharT2 >, const _CharT2 &)

basic_istream< _CharT2, _Traits2 > & getline (basic_istream< _CharT2, _Traits2 > &, basic_string< _CharT2, _Traits2, _Alloc > &, _CharT2)

class ios_base

class istreambuf_iterator< char_type, traits_type >

basic_istream< _CharT2, _Traits2 > & operator>> (basic_istream< _CharT2, _Traits2 > &, basic_string< _CharT2, _Traits2, _Alloc > &)

basic_istream< _CharT2, _Traits2 > & operator>> (basic_istream< _CharT2, _Traits2 > &, _CharT2 *)

class ostreambuf_iterator< char_type, traits_type >

locale getloc () const

locale pubimbue (const locale &__loc)

pos_type pubseekoff (off_type __off, ios_base::seekdir __way, ios_base::openmode __mode=ios_base::in|ios_base::out)

pos_type pubseekpos (pos_type __sp, ios_base::openmode __mode=ios_base::in|ios_base::out)

__streambuf_type * pubsetbuf (char_type *__s, streamsize __n)

int pubsync ()

locale _M_buf_locale

char_type * _M_in_beg

char_type * _M_in_cur

char_type * _M_in_end

char_type * _M_out_beg

char_type * _M_out_cur

char_type * _M_out_end

Detailed Description

template<typename _CharT, typename _Traits = std::char_traits<_CharT>> class __gnu_cxx::stdio_filebuf< _CharT, _Traits >

This GNU extension provides extensions for working with standard C FILE*'s and POSIX file descriptors. It must be instantiated by the user with the type of character used in the file stream, e.g., stdio_filebuf<char>.

Definition at line 52 of file stdio_filebuf.h.

Member Typedef Documentation

template<typename _CharT , typename _Traits = std::char_traits<_CharT>> typedef _CharT __gnu_cxx::stdio_filebuf< _CharT, _Traits >::char_type

These are standard types. They permit a standardized way of referring to names of (or names dependant on) the template parameters, which are specific to the implementation.

Reimplemented from std::basic_filebuf< _CharT, _Traits >.

Definition at line 56 of file stdio_filebuf.h.

template<typename _CharT , typename _Traits = std::char_traits<_CharT>> typedef traits_type::int_type __gnu_cxx::stdio_filebuf< _CharT, _Traits >::int_type

These are standard types. They permit a standardized way of referring to names of (or names dependant on) the template parameters, which are specific to the implementation.

Reimplemented from std::basic_filebuf< _CharT, _Traits >.

Definition at line 58 of file stdio_filebuf.h.

template<typename _CharT , typename _Traits = std::char_traits<_CharT>> typedef traits_type::off_type __gnu_cxx::stdio_filebuf< _CharT, _Traits >::off_type

These are standard types. They permit a standardized way of referring to names of (or names dependant on) the template parameters, which are specific to the implementation.

Reimplemented from std::basic_filebuf< _CharT, _Traits >.

Definition at line 60 of file stdio_filebuf.h.

template<typename _CharT , typename _Traits = std::char_traits<_CharT>> typedef traits_type::pos_type __gnu_cxx::stdio_filebuf< _CharT, _Traits >::pos_type

These are standard types. They permit a standardized way of referring to names of (or names dependant on) the template parameters, which are specific to the implementation.

Reimplemented from std::basic_filebuf< _CharT, _Traits >.

Definition at line 59 of file stdio_filebuf.h.

template<typename _CharT , typename _Traits = std::char_traits<_CharT>> typedef _Traits __gnu_cxx::stdio_filebuf< _CharT, _Traits >::traits_type

These are standard types. They permit a standardized way of referring to names of (or names dependant on) the template parameters, which are specific to the implementation.

Reimplemented from std::basic_filebuf< _CharT, _Traits >.

Definition at line 57 of file stdio_filebuf.h.

Constructor & Destructor Documentation

template<typename _CharT , typename _Traits = std::char_traits<_CharT>> __gnu_cxx::stdio_filebuf< _CharT, _Traits >::stdio_filebuf () [inline]

deferred initialization

Definition at line 67 of file stdio_filebuf.h.

template<typename _CharT , typename _Traits > __gnu_cxx::stdio_filebuf< _CharT, _Traits >::stdio_filebuf (int __fd, std::ios_base::openmode __mode, size_t __size = static_cast<size_t>(BUFSIZ)) [inline]

Parameters:

fd An open file descriptor.
mode Same meaning as in a standard filebuf.
size Optimal or preferred size of internal buffer, in chars.

This constructor associates a file stream buffer with an open POSIX file descriptor. The file descriptor will be automatically closed when the stdio_filebuf is closed/destroyed.

Definition at line 129 of file stdio_filebuf.h.

References std::basic_filebuf< _CharT, _Traits >::is_open().

template<typename _CharT , typename _Traits > __gnu_cxx::stdio_filebuf< _CharT, _Traits >::stdio_filebuf (std::__c_file * __f, std::ios_base::openmode __mode, size_t __size = static_cast<size_t>(BUFSIZ)) [inline]

Parameters:

f An open FILE*.
mode Same meaning as in a standard filebuf.
size Optimal or preferred size of internal buffer, in chars. Defaults to system's BUFSIZ.

This constructor associates a file stream buffer with an open C FILE*. The FILE* will not be automatically closed when the stdio_filebuf is closed/destroyed.

Definition at line 145 of file stdio_filebuf.h.

References std::basic_filebuf< _CharT, _Traits >::is_open().

template<typename _CharT , typename _Traits > __gnu_cxx::stdio_filebuf< _CharT, _Traits >::~stdio_filebuf () [inline, virtual]

Closes the external data stream if the file descriptor constructor was used.

Definition at line 124 of file stdio_filebuf.h.

Member Function Documentation

__filebuf_type* std::basic_filebuf< _CharT , _Traits >::close () throw () [inherited]

Closes the currently associated file.

Returns:

this on success, NULL on failure

If no file is currently open, this function immediately fails.

If a 'put buffer area' exists, overflow(eof) is called to flush all the characters. The file is then closed.

If any operations fail, this function also fails.

char_type* std::basic_streambuf< _CharT , _Traits >::eback () const [inline, protected, inherited]

Access to the get area.

These functions are only available to other protected functions, including derived classes.

•

eback() returns the beginning pointer for the input sequence

•

gptr() returns the next pointer for the input sequence

•

egptr() returns the end pointer for the input sequence

Definition at line 478 of file streambuf.

Referenced by std::basic_filebuf< _CharT, _Traits >::imbue(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::overflow(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekoff(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekpos(), std::basic_filebuf< _CharT, _Traits >::underflow(), and std::basic_filebuf< _CharT, _Traits >::xsgetn().

char_type* std::basic_streambuf< _CharT , _Traits >::egptr () const [inline, protected, inherited]

Access to the get area.

These functions are only available to other protected functions, including derived classes.

•

eback() returns the beginning pointer for the input sequence

•

gptr() returns the next pointer for the input sequence

•

egptr() returns the end pointer for the input sequence

Definition at line 484 of file streambuf.

Referenced by std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekoff(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekpos(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::underflow(), std::basic_filebuf< _CharT, _Traits >::underflow(), and std::basic_filebuf< _CharT, _Traits >::xsgetn().

char_type* std::basic_streambuf< _CharT , _Traits >::epptr () const [inline, protected, inherited]

Access to the put area.

These functions are only available to other protected functions, including derived classes.

•

pbase() returns the beginning pointer for the output sequence

•

pptr() returns the next pointer for the output sequence

•

epptr() returns the end pointer for the output sequence

Definition at line 531 of file streambuf.

Referenced by std::basic_stringbuf< _CharT, _Traits, _Alloc >::overflow().

template<typename _CharT , typename _Traits = std::char_traits<_CharT>> int __gnu_cxx::stdio_filebuf< _CharT, _Traits >::fd () [inline]

Returns:

The underlying file descriptor.

Once associated with an external data stream, this function can be used to access the underlying POSIX file descriptor. Note that there is no way for the library to track what you do with the descriptor, so be careful.

Definition at line 110 of file stdio_filebuf.h.

template<typename _CharT , typename _Traits = std::char_traits<_CharT>> std::__c_file* __gnu_cxx::stdio_filebuf< _CharT, _Traits >::file () [inline]

Returns:

The underlying FILE*.

This function can be used to access the underlying 'C' file pointer. Note that there is no way for the library to track what you do with the file, so be careful.

Definition at line 120 of file stdio_filebuf.h.

void std::basic_streambuf< _CharT , _Traits >::gbump (int __n) [inline, protected, inherited]

Moving the read position.

Parameters:

n The delta by which to move.

This just advances the read position without returning any data.

Definition at line 494 of file streambuf.

Referenced by std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekoff(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekpos(), and std::basic_filebuf< _CharT, _Traits >::xsgetn().

locale std::basic_streambuf< _CharT , _Traits >::getloc () const [inline, inherited]

Locale access.

Returns:

The current locale in effect.

If pubimbue(loc) has been called, then the most recent loc is returned. Otherwise the global locale in effect at the time of construction is returned.

Definition at line 241 of file streambuf.

char_type* std::basic_streambuf< _CharT , _Traits >::gptr () const [inline, protected, inherited]

Access to the get area.

These functions are only available to other protected functions, including derived classes.

•

eback() returns the beginning pointer for the input sequence

•

gptr() returns the next pointer for the input sequence

•

egptr() returns the end pointer for the input sequence

Definition at line 481 of file streambuf.

Referenced by std::basic_filebuf< _CharT, _Traits >::imbue(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::overflow(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekoff(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekpos(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::underflow(), std::basic_filebuf< _CharT, _Traits >::underflow(), and std::basic_filebuf< _CharT, _Traits >::xsgetn().

virtual void std::basic_filebuf< _CharT , _Traits >::imbue (const locale &) [protected, virtual, inherited]

Changes translations.

Parameters:

loc A new locale.

Translations done during I/O which depend on the current locale are changed by this call. The standard adds, 'Between invocations of this function a class derived from streambuf can safely cache results of calls to locale functions and to members of facets so obtained.'

Note:

Base class version does nothing.

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

streamsize std::basic_streambuf< _CharT , _Traits >::in_avail () [inline, inherited]

Looking ahead into the stream.

Returns:

The number of characters available.

If a read position is available, returns the number of characters available for reading before the buffer must be refilled. Otherwise returns the derived showmanyc().

Definition at line 281 of file streambuf.

bool std::basic_filebuf< _CharT , _Traits >::is_open () const throw () [inline, inherited]

Returns true if the external file is open.

Definition at line 248 of file fstream.

Referenced by __gnu_cxx::stdio_filebuf< _CharT, _Traits >::stdio_filebuf().

__filebuf_type* std::basic_filebuf< _CharT , _Traits >::open (const char * __s, ios_base::openmode __mode) [inherited]

Opens an external file.

Parameters:

s The name of the file.
mode The open mode flags.

Returns:

this on success, NULL on failure

If a file is already open, this function immediately fails. Otherwise it tries to open the file named s using the flags given in mode.

Table 92, adapted here, gives the relation between openmode combinations and the equivalent fopen() flags. (NB: lines in|out|app and binary|in|out|app per DR 596) +---------------------------------------------------------+ | ios_base Flag combination stdio equivalent | |binary in out trunc app | +---------------------------------------------------------+ | + 'w' | | + + 'a' | | + + 'w' | | + 'r' | | + + 'r+' | | + + + 'w+' | | + + + 'a+' | +---------------------------------------------------------+ | + + 'wb' | | + + + 'ab' | | + + + 'wb' | | + + 'rb' | | + + + 'r+b' | | + + + + 'w+b' | | + + + + 'a+b' | +---------------------------------------------------------+

virtual int_type std::basic_filebuf< _CharT , _Traits >::overflow (int_type = _Traits::eof()) [protected, virtual, inherited]

Consumes data from the buffer; writes to the controlled sequence.

Parameters:

c An additional character to consume.

Returns:

eof() to indicate failure, something else (usually c, or not_eof())

Informally, this function is called when the output buffer is full (or does not exist, as buffering need not actually be done). If a buffer exists, it is 'consumed', with 'some effect' on the controlled sequence. (Typically, the buffer is written out to the sequence verbatim.) In either case, the character c is also written out, if c is not eof().

For a formal definiton of this function, see a good text such as Langer & Kreft, or [27.5.2.4.5]/3-7.

A functioning output streambuf can be created by overriding only this function (no buffer area will be used).

Note:

Base class version does nothing, returns eof().

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

virtual int_type std::basic_filebuf< _CharT , _Traits >::pbackfail (int_type = _Traits::eof()) [protected, virtual, inherited]

Tries to back up the input sequence.

Parameters:

c The character to be inserted back into the sequence.

Returns:

eof() on failure, 'some other value' on success

Postcondition:

The constraints of gptr(), eback(), and pptr() are the same as for underflow().

Note:

Base class version does nothing, returns eof().

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

char_type* std::basic_streambuf< _CharT , _Traits >::pbase () const [inline, protected, inherited]

Access to the put area.

These functions are only available to other protected functions, including derived classes.

•

pbase() returns the beginning pointer for the output sequence

•

pptr() returns the next pointer for the output sequence

•

epptr() returns the end pointer for the output sequence

Definition at line 525 of file streambuf.

Referenced by std::basic_stringbuf< _CharT, _Traits, _Alloc >::overflow(), std::basic_filebuf< _CharT, _Traits >::overflow(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekoff(), and std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekpos().

void std::basic_streambuf< _CharT , _Traits >::pbump (int __n) [inline, protected, inherited]

Moving the write position.

Parameters:

n The delta by which to move.

This just advances the write position without returning any data.

Definition at line 541 of file streambuf.

Referenced by std::basic_stringbuf< _CharT, _Traits, _Alloc >::overflow(), std::basic_filebuf< _CharT, _Traits >::overflow(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekoff(), and std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekpos().

char_type* std::basic_streambuf< _CharT , _Traits >::pptr () const [inline, protected, inherited]

Access to the put area.

These functions are only available to other protected functions, including derived classes.

•

pbase() returns the beginning pointer for the output sequence

•

pptr() returns the next pointer for the output sequence

•

epptr() returns the end pointer for the output sequence

Definition at line 528 of file streambuf.

Referenced by std::basic_stringbuf< _CharT, _Traits, _Alloc >::overflow(), std::basic_filebuf< _CharT, _Traits >::overflow(), std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekoff(), and std::basic_stringbuf< _CharT, _Traits, _Alloc >::seekpos().

locale std::basic_streambuf< _CharT , _Traits >::pubimbue (const locale & __loc) [inline, inherited]

Entry point for imbue().

Parameters:

loc The new locale.

Returns:

The previous locale.

Calls the derived imbue(loc).

Definition at line 224 of file streambuf.

pos_type std::basic_streambuf< _CharT , _Traits >::pubseekoff (off_type __off, ios_base::seekdir __way, ios_base::openmode __mode = ios_base::in | ios_base::out) [inline, inherited]

Locale access.

Returns:

The current locale in effect.

If pubimbue(loc) has been called, then the most recent loc is returned. Otherwise the global locale in effect at the time of construction is returned.

Definition at line 258 of file streambuf.

pos_type std::basic_streambuf< _CharT , _Traits >::pubseekpos (pos_type __sp, ios_base::openmode __mode = ios_base::in | ios_base::out) [inline, inherited]

Locale access.

Returns:

The current locale in effect.

If pubimbue(loc) has been called, then the most recent loc is returned. Otherwise the global locale in effect at the time of construction is returned.

Definition at line 263 of file streambuf.

__streambuf_type* std::basic_streambuf< _CharT , _Traits >::pubsetbuf (char_type * __s, streamsize __n) [inline, inherited]

Entry points for derived buffer functions.

The public versions of pubfoo dispatch to the protected derived foo member functions, passing the arguments (if any) and returning the result unchanged.

Definition at line 254 of file streambuf.

int std::basic_streambuf< _CharT , _Traits >::pubsync () [inline, inherited]

Locale access.

Returns:

The current locale in effect.

If pubimbue(loc) has been called, then the most recent loc is returned. Otherwise the global locale in effect at the time of construction is returned.

Definition at line 268 of file streambuf.

int_type std::basic_streambuf< _CharT , _Traits >::sbumpc () [inline, inherited]

Getting the next character.

Returns:

The next character, or eof.

If the input read position is available, returns that character and increments the read pointer, otherwise calls and returns uflow().

Definition at line 313 of file streambuf.

virtual pos_type std::basic_filebuf< _CharT , _Traits >::seekoff (off_type, ios_base::seekdir, ios_base::openmode = ios_base::in | ios_base::out) [protected, virtual, inherited]

Alters the stream positions.

Each derived class provides its own appropriate behavior.

Note:

Base class version does nothing, returns a pos_type that represents an invalid stream position.

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

virtual pos_type std::basic_filebuf< _CharT , _Traits >::seekpos (pos_type, ios_base::openmode = ios_base::in | ios_base::out) [protected, virtual, inherited]

Alters the stream positions.

Each derived class provides its own appropriate behavior.

Note:

Base class version does nothing, returns a pos_type that represents an invalid stream position.

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

virtual __streambuf_type* std::basic_filebuf< _CharT , _Traits >::setbuf (char_type * __s, streamsize __n) [protected, virtual, inherited]

Manipulates the buffer.

Parameters:

s Pointer to a buffer area.
n Size of s.

Returns:

this

If no file has been opened, and both s and n are zero, then the stream becomes unbuffered. Otherwise, s is used as a buffer; see http://gcc.gnu.org/onlinedocs/libstdc++/27_io/howto.html#2 for more.

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

void std::basic_streambuf< _CharT , _Traits >::setg (char_type * __gbeg, char_type * __gnext, char_type * __gend) [inline, protected, inherited]

Setting the three read area pointers.

Parameters:

gbeg A pointer.
gnext A pointer.
gend A pointer.

Postcondition:

gbeg == eback(), gnext == gptr(), and gend == egptr()

Definition at line 505 of file streambuf.

void std::basic_streambuf< _CharT , _Traits >::setp (char_type * __pbeg, char_type * __pend) [inline, protected, inherited]

Setting the three write area pointers.

Parameters:

pbeg A pointer.
pend A pointer.

Postcondition:

pbeg == pbase(), pbeg == pptr(), and pend == epptr()

Definition at line 551 of file streambuf.

int_type std::basic_streambuf< _CharT , _Traits >::sgetc () [inline, inherited]

Getting the next character.

Returns:

The next character, or eof.

If the input read position is available, returns that character, otherwise calls and returns underflow(). Does not move the read position after fetching the character.

Definition at line 335 of file streambuf.

streamsize std::basic_streambuf< _CharT , _Traits >::sgetn (char_type * __s, streamsize __n) [inline, inherited]

Entry point for xsgetn.

Parameters:

s A buffer area.
n A count.

Returns xsgetn(s,n). The effect is to fill s[0] through s[n-1] with characters from the input sequence, if possible.

Definition at line 354 of file streambuf.

virtual streamsize std::basic_filebuf< _CharT , _Traits >::showmanyc () [protected, virtual, inherited]

Investigating the data available.

Returns:

An estimate of the number of characters available in the input sequence, or -1.

Note:

Base class version does nothing, returns zero.
The standard adds that 'the intention is not only that the calls [to underflow or uflow] will not return eof() but that they will return 'immediately'.
The standard adds that 'the morphemes of showmanyc are 'es-how-many-see', not 'show-manic'.

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

int_type std::basic_streambuf< _CharT , _Traits >::snextc () [inline, inherited]

Getting the next character.

Returns:

The next character, or eof.

Calls sbumpc(), and if that function returns traits::eof(), so does this function. Otherwise, sgetc().

Definition at line 295 of file streambuf.

int_type std::basic_streambuf< _CharT , _Traits >::sputbackc (char_type __c) [inline, inherited]

Pushing characters back into the input stream.

Parameters:

c The character to push back.

Returns:

The previous character, if possible.

Similar to sungetc(), but c is pushed onto the stream instead of 'the previous character'. If successful, the next character fetched from the input stream will be c.

Definition at line 368 of file streambuf.

int_type std::basic_streambuf< _CharT , _Traits >::sputc (char_type __c) [inline, inherited]

Entry point for all single-character output functions.

Parameters:

c A character to output.

Returns:

c, if possible.

One of two public output functions.

If a write position is available for the output sequence (i.e., the buffer is not full), stores c in that position, increments the position, and returns traits::to_int_type(c). If a write position is not available, returns overflow(c).

Definition at line 420 of file streambuf.

streamsize std::basic_streambuf< _CharT , _Traits >::sputn (const char_type * __s, streamsize __n) [inline, inherited]

Entry point for all single-character output functions.

Parameters:

s A buffer read area.
n A count.

One of two public output functions.

Returns xsputn(s,n). The effect is to write s[0] through s[n-1] to the output sequence, if possible.

Definition at line 446 of file streambuf.

void std::basic_streambuf< _CharT , _Traits >::stossc () [inline, inherited]

Tosses a character.

Advances the read pointer, ignoring the character that would have been read.

See http://gcc.gnu.org/ml/libstdc++/2002-05/msg00168.html

Note:

This function has been deprecated by the standard. You must define _GLIBCXX_DEPRECATED to make this visible; see c++config.h.

Definition at line 782 of file streambuf.

int_type std::basic_streambuf< _CharT , _Traits >::sungetc () [inline, inherited]

Moving backwards in the input stream.

Returns:

The previous character, if possible.

If a putback position is available, this function decrements the input pointer and returns that character. Otherwise, calls and returns pbackfail(). The effect is to 'unget' the last character 'gotten'.

Definition at line 393 of file streambuf.

virtual int std::basic_filebuf< _CharT , _Traits >::sync (void) [protected, virtual, inherited]

Synchronizes the buffer arrays with the controlled sequences.

Returns:

-1 on failure.

Each derived class provides its own appropriate behavior, including the definition of 'failure'.

Note:

Base class version does nothing, returns zero.

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

virtual int_type std::basic_streambuf< _CharT , _Traits >::uflow () [inline, protected, virtual, inherited]

Fetches more data from the controlled sequence.

Returns:

The first character from the pending sequence.

Informally, this function does the same thing as underflow(), and in fact is required to call that function. It also returns the new character, like underflow() does. However, this function also moves the read position forward by one.

Reimplemented in __gnu_cxx::stdio_sync_filebuf< _CharT, _Traits >.

Definition at line 696 of file streambuf.

virtual int_type std::basic_filebuf< _CharT , _Traits >::underflow () [protected, virtual, inherited]

Fetches more data from the controlled sequence.

Returns:

The first character from the pending sequence.

Informally, this function is called when the input buffer is exhausted (or does not exist, as buffering need not actually be done). If a buffer exists, it is 'refilled'. In either case, the next available character is returned, or traits::eof() to indicate a null pending sequence.

For a formal definiton of the pending sequence, see a good text such as Langer & Kreft, or [27.5.2.4.3]/7-14.

A functioning input streambuf can be created by overriding only this function (no buffer area will be used). For an example, see http://gcc.gnu.org/onlinedocs/libstdc++/27_io/howto.html#6

Note:

Base class version does nothing, returns eof().

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

virtual streamsize std::basic_filebuf< _CharT , _Traits >::xsgetn (char_type * __s, streamsize __n) [protected, virtual, inherited]

Multiple character extraction.

Parameters:

s A buffer area.
n Maximum number of characters to assign.

Returns:

The number of characters assigned.

Fills s[0] through s[n-1] with characters from the input sequence, as if by sbumpc(). Stops when either n characters have been copied, or when traits::eof() would be copied.

It is expected that derived classes provide a more efficient implementation by overriding this definition.

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

virtual streamsize std::basic_filebuf< _CharT , _Traits >::xsputn (const char_type * __s, streamsize __n) [protected, virtual, inherited]

Multiple character insertion.

Parameters:

s A buffer area.
n Maximum number of characters to write.

Returns:

The number of characters written.

Writes s[0] through s[n-1] to the output sequence, as if by sputc(). Stops when either n characters have been copied, or when sputc() would return traits::eof().

It is expected that derived classes provide a more efficient implementation by overriding this definition.

Reimplemented from std::basic_streambuf< _CharT, _Traits >.

Member Data Documentation

locale std::basic_streambuf< _CharT , _Traits >::_M_buf_locale [protected, inherited]

Locale access.

Returns:

The current locale in effect.

If pubimbue(loc) has been called, then the most recent loc is returned. Otherwise the global locale in effect at the time of construction is returned.

Definition at line 207 of file streambuf.

Referenced by std::basic_filebuf< _CharT, _Traits >::basic_filebuf().

char_type* std::basic_streambuf< _CharT , _Traits >::_M_in_beg [protected, inherited]

Locale access.

Returns:

The current locale in effect.

If pubimbue(loc) has been called, then the most recent loc is returned. Otherwise the global locale in effect at the time of construction is returned.

Definition at line 195 of file streambuf.

char_type* std::basic_streambuf< _CharT , _Traits >::_M_in_cur [protected, inherited]

Locale access.

Returns:

The current locale in effect.

If pubimbue(loc) has been called, then the most recent loc is returned. Otherwise the global locale in effect at the time of construction is returned.

Definition at line 196 of file streambuf.

char_type* std::basic_streambuf< _CharT , _Traits >::_M_in_end [protected, inherited]

Locale access.

Returns:

The current locale in effect.

If pubimbue(loc) has been called, then the most recent loc is returned. Otherwise the global locale in effect at the time of construction is returned.

Definition at line 197 of file streambuf.

char_type* std::basic_streambuf< _CharT , _Traits >::_M_out_beg [protected, inherited]

Locale access.

Returns:

The current locale in effect.

If pubimbue(loc) has been called, then the most recent loc is returned. Otherwise the global locale in effect at the time of construction is returned.

Definition at line 198 of file streambuf.

char_type* std::basic_streambuf< _CharT , _Traits >::_M_out_cur [protected, inherited]

Locale access.

Returns:

The current locale in effect.

If pubimbue(loc) has been called, then the most recent loc is returned. Otherwise the global locale in effect at the time of construction is returned.

Definition at line 199 of file streambuf.

char_type* std::basic_streambuf< _CharT , _Traits >::_M_out_end [protected, inherited]

Locale access.

Returns:

The current locale in effect.

If pubimbue(loc) has been called, then the most recent loc is returned. Otherwise the global locale in effect at the time of construction is returned.

Definition at line 200 of file streambuf.

Author

Generated automatically by Doxygen for libstdc++ from the source code.