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FILE(1)                     General Commands Manual                    FILE(1)



NAME
       file - determine the type of a file by examining its contents

SYNOPSIS
       file [ -f ffile ] [ -cL ] [ -m mfile ] filename...

DESCRIPTION
       file  performs  a  series  of  tests  on each filename in an attempt to
       determine what it contains.  If the contents of a  file  appear  to  be
       ASCII  text,  file  examines the first 512 bytes and tries to guess its
       language.

       file uses the file /etc/magic to identify files that have some sort  of
       magic number, that is, any file containing a numeric or string constant
       that indicates its type.

OPTIONS
       -c     Check for format errors in the magic number file.   For  reasons
              of  efficiency, this validation is not normally carried out.  No
              file type-checking is done under -c.

       -f ffile
              Get a list of filenames to identify from ffile.

       -L     If a file is a symbolic link, test the file the link  references
              rather than the link itself.

       -m mfile
              Use mfile as the name of an alternate magic number file.

EXAMPLE
       This example illustrates the use of file on all the files in a specific
       user's directory:
              example% pwd
              /usr/blort/misc
              example% file  *

              code:               mc68020 demand paged executable

              code.c:             c program text

              counts:             ascii text

              doc:                roff, nroff , or eqn input text

              empty.file:         empty

              libz:               archive random library

              memos:              directory

              project:            symbolic link to /usr/project

              script:             executable shell script

              titles:             ascii text

              s5.stuff:           cpio archive

              example%

ENVIRONMENT
       The environment variables LC_CTYPE, LANG, and  LC_default  control  the
       character  classification  throughout  file.   On  entry to file, these
       environment variables are checked in  the  following  order:  LC_CTYPE,
       LANG,  and LC_default.  When a valid value is found, remaining environ-
       ment variables for character classification are ignored.  For  example,
       a  new  setting  for LANG does not override the current valid character
       classification rules of LC_CTYPE.  When none of the  values  is  valid,
       the shell character classification defaults to the POSIX.1 "C" locale.

FILES
       /etc/magic

SEE ALSO
       locale(5), magic(5)

BUGS
       file  often makes mistakes.  In particular, it often suggests that com-
       mand files are C programs.

       Does not recognize Pascal or LISP.



                                2 October 1989                         FILE(1)