file [-bchiklLNnprsvz0] [--apple] [--mime-encoding] [--mime-type]
          [-e testname] [-F separator] [-f namefile] [-m magicfiles]
          [-R maxrecursion] file ...
     file -C [-m magicfiles]
     file [--help]

     This manual page documents version 5.09 of the file command.

     file tests each argument in an attempt to classify it.  There are three
     sets of tests, performed in this order: filesystem tests, magic tests,
     and language tests.  The first test that succeeds causes the file type to
     be printed.

     The type printed will usually contain one of the words text (the file
     contains only printing characters and a few common control characters and
     is probably safe to read on an ASCII terminal), executable (the file con-
     tains the result of compiling a program in a form understandable to some
     UNIX kernel or another), or data meaning anything else (data is usually
     ``binary'' or non-printable).  Exceptions are well-known file formats
     (core files, tar archives) that are known to contain binary data.  When
     adding local definitions to /etc/magic, make sure to preserve these
     keywords.  Users depend on knowing that all the readable files in a
     directory have the word ``text'' printed.  Don't do as Berkeley did and
     change ``shell commands text'' to ``shell script''.

     The filesystem tests are based on examining the return from a stat(2)
     system call.  The program checks to see if the file is empty, or if it's
     some sort of special file.  Any known file types appropriate to the sys-
     tem you are running on (sockets, symbolic links, or named pipes (FIFOs)
     on those systems that implement them) are intuited if they are defined in
     the system header file <sys/stat.h>.

     The magic tests are used to check for files with data in particular fixed
     formats.  The canonical example of this is a binary executable (compiled
     program) a.out file, whose format is defined in <elf.h>, <a.out.h> and
     possibly <exec.h> in the standard include directory.  These files have a
     ``magic number'' stored in a particular place near the beginning of the
     file that tells the UNIX operating system that the file is a binary exe-
     cutable, and which of several types thereof.  The concept of a ``magic''
     has been applied by extension to data files.  Any file with some invari-
     ant identifier at a small fixed offset into the file can usually be
     described in this way.  The information identifying these files is read
     from /etc/magic and the compiled magic file /usr/share/misc/magic.mgc, or
     the files in the directory /usr/share/misc/magic if the compiled file
     does not exist.  In addition, if $HOME/.magic.mgc or $HOME/.magic exists,
     it will be used in preference to the system magic files.

     If a file does not match any of the entries in the magic file, it is
     examined to see if it seems to be a text file.  ASCII, ISO-8859-x, non-
     ISO 8-bit extended-ASCII character sets (such as those used on Macintosh
     and IBM PC systems), UTF-8-encoded Unicode, UTF-16-encoded Unicode, and
     EBCDIC character sets can be distinguished by the different ranges and
     sequences of bytes that constitute printable text in each set.  If a file
     guage tests look for particular strings (cf.  <names.h>) that can appear
     anywhere in the first few blocks of a file.  For example, the keyword .br
     indicates that the file is most likely a troff(1) input file, just as the
     keyword struct indicates a C program.  These tests are less reliable than
     the previous two groups, so they are performed last.  The language test
     routines also test for some miscellany (such as tar(1) archives).

     Any file that cannot be identified as having been written in any of the
     character sets listed above is simply said to be ``data''.

     -b, --brief
             Do not prepend filenames to output lines (brief mode).

     -C, --compile
             Write a magic.mgc output file that contains a pre-parsed version
             of the magic file or directory.

     -c, --checking-printout
             Cause a checking printout of the parsed form of the magic file.
             This is usually used in conjunction with the -m flag to debug a
             new magic file before installing it.

     -e, --exclude testname
             Exclude the test named in testname from the list of tests made to
             determine the file type.  Valid test names are:

             apptype   EMX application type (only on EMX).

             ascii     Various types of text files (this test will try to
                       guess the text encoding, irrespective of the setting of
                       the 'encoding' option).

             encoding  Different text encodings for soft magic tests.

             tokens    Looks for known tokens inside text files.

             cdf       Prints details of Compound Document Files.

             compress  Checks for, and looks inside, compressed files.

             elf       Prints ELF file details.

             soft      Consults magic files.

             tar       Examines tar files.

     -F, --separator separator
             Use the specified string as the separator between the filename
             and the file result returned.  Defaults to ':'.

     -f, --files-from namefile
             Read the names of the files to be examined from namefile (one per
             line) before the argument list.  Either namefile or at least one

     --mime-type, --mime-encoding
             Like -i, but print only the specified element(s).

     -k, --keep-going
             Don't stop at the first match, keep going.  Subsequent matches
             will be have the string '\012- ' prepended.  (If you want a new-
             line, see the -r option.)

     -l, --list
             Print information about the strength of each magic pattern.

     -L, --dereference
             option causes symlinks to be followed, as the like-named option
             in ls(1) (on systems that support symbolic links).  This is the
             default if the environment variable POSIXLY_CORRECT is defined.

     -l      Shows sorted patterns list in the order which is used for the

     -m, --magic-file magicfiles
             Specify an alternate list of files and directories containing
             magic.  This can be a single item, or a colon-separated list.  If
             a compiled magic file is found alongside a file or directory, it
             will be used instead.

     -N, --no-pad
             Don't pad filenames so that they align in the output.

     -n, --no-buffer
             Force stdout to be flushed after checking each file.  This is
             only useful if checking a list of files.  It is intended to be
             used by programs that want filetype output from a pipe.

     -p, --preserve-date
             On systems that support utime(3) or utimes(2), attempt to pre-
             serve the access time of files analyzed, to pretend that file
             never read them.

     -r, --raw
             Don't translate unprintable characters to \ooo.  Normally file
             translates unprintable characters to their octal representation.

     -R, --recursion maxlevel
             Set the maximum recursion level for indirect type magic or
             name/use entry invocations.  The default is 15.

     -s, --special-files
             Normally, file only attempts to read and determine the type of
             argument files which stat(2) reports are ordinary files.  This
             prevents problems, because reading special files may have pecu-
             liar consequences.  Specifying the -s option causes file to also
             read argument files which are block or character special files.
             This is useful for determining the filesystem types of the data
             Output a null character '\0' after the end of the filename.  Nice
             to cut(1) the output.  This does not affect the separator which
             is still printed.

     --help  Print a help message and exit.

     /usr/share/misc/magic.mgc  Default compiled list of magic.
     /usr/share/misc/magic      Directory containing default magic files.

     The environment variable MAGIC can be used to set the default magic file
     name.  If that variable is set, then file will not attempt to open
     $HOME/.magic.  file adds ``.mgc'' to the value of this variable as appro-
     priate.  However, file has to exist in order for file.mime to be consid-
     ered.  The environment variable POSIXLY_CORRECT controls (on systems that
     support symbolic links), whether file will attempt to follow symlinks or
     not.  If set, then file follows symlink, otherwise it does not.  This is
     also controlled by the -L and -h options.

     magic(5), hexdump(1), od(1), strings(1),

     This program is believed to exceed the System V Interface Definition of
     FILE(CMD), as near as one can determine from the vague language contained
     therein.  Its behavior is mostly compatible with the System V program of
     the same name.  This version knows more magic, however, so it will pro-
     duce different (albeit more accurate) output in many cases.

     The one significant difference between this version and System V is that
     this version treats any white space as a delimiter, so that spaces in
     pattern strings must be escaped.  For example,

           >10     string  language impress        (imPRESS data)

     in an existing magic file would have to be changed to

           >10     string  language\ impress       (imPRESS data)

     In addition, in this version, if a pattern string contains a backslash,
     it must be escaped.  For example

           0       string          \begindata      Andrew Toolkit document

     in an existing magic file would have to be changed to

           0       string          \\begindata     Andrew Toolkit document

     SunOS releases 3.2 and later from Sun Microsystems include a file command
     derived from the System V one, but with some extensions.  This version
     differs from Sun's only in minor ways.  It includes the extension of the
     '&' operator, used as, for example,

           $ file file.c file /dev/{wd0a,hda}
           file.c:   C program text
           file:     ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV),
                     dynamically linked (uses shared libs), stripped
           /dev/wd0a: block special (0/0)
           /dev/hda: block special (3/0)

           $ file -s /dev/wd0{b,d}
           /dev/wd0b: data
           /dev/wd0d: x86 boot sector

           $ file -s /dev/hda{,1,2,3,4,5,6,7,8,9,10}
           /dev/hda:   x86 boot sector
           /dev/hda1:  Linux/i386 ext2 filesystem
           /dev/hda2:  x86 boot sector
           /dev/hda3:  x86 boot sector, extended partition table
           /dev/hda4:  Linux/i386 ext2 filesystem
           /dev/hda5:  Linux/i386 swap file
           /dev/hda6:  Linux/i386 swap file
           /dev/hda7:  Linux/i386 swap file
           /dev/hda8:  Linux/i386 swap file
           /dev/hda9:  empty
           /dev/hda10: empty

           $ file -i file.c file /dev/{wd0a,hda}
           file.c:      text/x-c
           file:        application/x-executable
           /dev/hda:    application/x-not-regular-file
           /dev/wd0a:   application/x-not-regular-file

     There has been a file command in every UNIX since at least Research
     Version 4 (man page dated November, 1973).  The System V version intro-
     duced one significant major change: the external list of magic types.
     This slowed the program down slightly but made it a lot more flexible.

     This program, based on the System V version, was written by Ian Darwin
     <> without looking at anybody else's source code.

     John Gilmore revised the code extensively, making it better than the
     first version.  Geoff Collyer found several inadequacies and provided
     some magic file entries.  Contributions by the '&' operator by Rob McMa-
     hon, <>, 1989.

     Guy Harris, <>, made many changes from 1993 to the present.

     Primary development and maintenance from 1990 to the present by Christos
     Zoulas <>.

     Altered by Chris Lowth <>, 2000: handle the -i option to
     output mime type strings, using an alternative magic file and internal
     long to include here.  You know who you are; thank you.  Many contribu-
     tors are listed in the source files.

     Copyright (c) Ian F. Darwin, Toronto, Canada, 1986-1999.  Covered by the
     standard Berkeley Software Distribution copyright; see the file COPYING
     in the source distribution.

     The files tar.h and is_tar.c were written by John Gilmore from his pub-
     lic-domain tar(1) program, and are not covered by the above license.

     file returns 0 on success, and non-zero on error.

     Please report bugs and send patches to the bug tracker at or the mailing list at <>.

     Fix output so that tests for MIME and APPLE flags are not needed all over
     the place, and actual output is only done in one place. This needs a
     design. Suggestion: push possible outputs on to a list, then pick the
     last-pushed (most specific, one hopes) value at the end, or use a default
     if the list is empty. This should not slow down evaluation.

     Continue to squash all magic bugs. See Debian BTS for a good source.

     Store arbitrarily long strings, for example for %s patterns, so that they
     can be printed out. Fixes Debian bug #271672. Would require more complex
     store/load code in apprentice.

     Add syntax for relative offsets after current level (Debian bug #466037).

     Make file -ki work, i.e. give multiple MIME types.

     Add a zip library so we can peek inside Office2007 documents to figure
     out what they are.

     Add an option to print URLs for the sources of the file descriptions.

     You can obtain the original author's latest version by anonymous FTP on in the directory /pub/file/file-X.YZ.tar.gz.

BSD                             April 20, 2011                             BSD
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