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xfm_magic

NAME

xfm_magic - xfm's magic file format

DESCRIPTION

xfm(1) and xfmtype(1) read files in this format to determine the mime type of a file, which again is used to determine what command to open it with.

The format of the configuration file is the same as the magic(5) with the following additions and differences:

include: directive

If a line starts with include: the rest of the line is treated as filename of another magic file to be read and processed before processing this file continues.

Included files can be include files again. Thus a user specific file can
include: /etc/X11/xfm/xfm_magic
to get the system wide xfm defaults and this file again
include: /usr/share/file/magic.mime
to get the system wide system defaults.

mode type field.

Similar to long type, but offset is ignored. The test is performed against the st_mode field of the stat structure obtained using stat(2) system call. This allows testing for directories, fifos ... as well as for file permissions.

lmode type field.

Similar to mode type, but using lstat(2) instead of stat(2). This allows testing for symbolic links.

regexp type field.

The value field must be a proper regular expression. The bytes starting at offset are matched against it. If the match succeeds, then a regsub(3) is performed on message yielding the final message. If the type field is of the form regexp&nnn where nnn is a positive number, then that number controls the amount of data scanned for the matching, otherwise a compile defined value (currently 256) is used.

long and short byte order.

xfmtype always reads longs and shorts using MSB-first order. This makes configuration files portable to all architectures, but some entries in original magic(5) files might be wrong.

Continuation lines.

If a line ends with a backslash character (\), it is continued with the following line. The maximum length of a line is 1024 characters (counting also characters in continuation lines).

FILES

$HOME/.xfm/xfm_magic

Default location xfm(1) looks for a file of this format. (Note that xfmtype(1) only reads files specified with -m on the command line.)

/etc/X11/xfm/xfm_magic

System wide default file if there is no user specific one.

SEE ALSO

xfm(1), xfmtype(1), file(1), magic(5), stat(2), lstat(2).

COPYRIGHT

Copyright (c) 1995 CNM-US
Copyright (c) 1995 Juan D. Martin

AUTHOR

Juan D. Martin (juando@cnm.us.es)
(but modified heavily by Bernhard R. Link)