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file(1)                          User Commands                         file(1)



NAME
       file - determine file type

SYNOPSIS
       /usr/bin/file [-dh] [-m mfile] [-M Mfile] [-f ffile] file...

       /usr/bin/file [-dh] [-m mfile] [-M Mfile] -f ffile

       /usr/bin/file -i [-h] [-f ffile] file...

       /usr/bin/file -i [-h] -f ffile

       /usr/bin/file -c [-d] [-m mfile] [-M Mfile]

       /usr/xpg4/bin/file [-dh] [-m mfile] [-M Mfile] [-f ffile] file...

       /usr/xpg4/bin/file [-dh] [-m mfile] [-M Mfile] -f ffile

       /usr/xpg4/bin/file -i [-h] [-f ffile] file...

       /usr/xpg4/bin/file -i [-h] -f ffile

       /usr/xpg4/bin/file -c [-d] [-m mfile] [-M Mfile]

DESCRIPTION
       The  file  utility  performs a series of tests on each file supplied by
       file and, optionally, on each file listed in ffile  in  an  attempt  to
       classify  it. If the file is not a regular file, its file type is iden-
       tified. The file types directory, FIFO, block  special,  and  character
       special  are  identified as such. If the file is a regular file and the
       file is zero-length, it is identified as an empty file.

       If file appears to be a text file, file examines the  first  512  bytes
       and  tries to determine its programming language. If file is a symbolic
       link, by default the link is followed and file tests the file to  which
       the symbolic link refers.

       If  file  is  a  relocatable object, executable, or shared object, file
       prints out information regarding  the  file's  execution  requirements.
       This  information  includes the machine class, byte-ordering, static or
       dynamic linkage, and any software or hardware capability requirements.

       By  default,  file  will  try  to  use   the   localized   magic   file
       /usr/lib/locale/locale/LC_MESSAGES/magic,  if  it  exists,  to identify
       files that have a magic number. For example, in  the  Japanese  locale,
       file  will try to use /usr/lib/locale/ja/LC_MESSAGES/magic. If a local-
       ized magic file does not exist, file will utilize /etc/magic.  A  magic
       number  is  a  numeric or string constant that indicates the file type.
       See magic(4) for an explanation of the format of /etc/magic.

       If file does not exist, cannot be read, or its file status could not be
       determined, it is not considered an error that affects the exit status.
       The output will indicate that the file was processed, but that its type
       could not be determined.

OPTIONS
       The following options are supported:

       -c              Checks the magic file for format errors. For reasons of
                       efficiency, this validation  is  normally  not  carried
                       out.



       -d              Applies  any  position-sensitive  and context-sensitive
                       default system tests to the file.



       -f ffile        ffile contains a list of the files to be examined.



       -h              When a symbolic link is encountered, this option  iden-
                       tifies the file as a symbolic link. If -h is not speci-
                       fied and file is a symbolic link that refers to a  non-
                       existent  file, the file utility identifies the file as
                       a symbolic link, as if -h had been specified.



       -i              If a file is a  regular  file,  this  option  does  not
                       attempt to classify the type of file further, but iden-
                       tifies the file as a "regular file".



       -m mfile
                       /usr/bin/file

                           Uses mfile as an alternate magic file,  instead  of
                           /etc/magic.




                       /usr/xpg4/bin/file

                           Specifies  the  name of a file containing position-
                           sensitive tests that are applied to a file in order
                           to  classify it (see magic(4)). If the -m option is
                           specified without specifying the -d option  or  the
                           -M  option, position-sensitive default system tests
                           are  applied  after  the  position-sensitive  tests
                           specified by the -m option.



       -M Mfile        Specifies the name of a file containing position-sensi-
                       tive tests that are applied to a file in order to clas-
                       sify  it  (see magic(4)). No position-sensitive default
                       system tests nor context-sensitive default system tests
                       are applied unless the -d option is also specified.



       If  the  -M  option  is specified with the -d option, the -m option, or
       both, or if the -m option is specified with the -d option, the concate-
       nation  of  the  position-sensitive tests specified by these options is
       applied in the order specified by the appearance of these options.

OPERANDS
       The following operands are supported:

       file            A path name of a file to be tested.



USAGE
       See largefile(5) for the description  of  the  behavior  of  file  when
       encountering files greater than or equal to 2 Gbyte ( 2**31 bytes).

EXAMPLES
       Example 1: Binary executable files

       Determine if an argument is a binary executable file:

       file "$1" | grep -Fq executable &&&&
                 printf "%s is executable.\n" "$1"

ENVIRONMENT VARIABLES
       See  environ(5) for descriptions of the following environment variables
       that affect the execution of file: LANG, LC_ALL, LC_CTYPE, LC_MESSAGES,
       and NLSPATH.

EXIT STATUS
       The following exit values are returned:

       0        Successful completion.



       >>0       An error occurred.



FILES
       /etc/magic      file's magic number file



ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:


       tab()     allbox;     cw(2.750000i)|    cw(2.750000i)    lw(2.750000i)|
       lw(2.750000i).   ATTRIBUTE  TYPEATTRIBUTE   VALUE   AvailabilitySUNWcsu
       CSIenabled Interface StabilityStandard


SEE ALSO
       elfdump(1),  ls(1),  magic(4), attributes(5), environ(5), largefile(5),
       standards(5)



SunOS 5.10                       16 July 2004                          file(1)