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file(1) [v7 man page]

FILE(1) 						      General Commands Manual							   FILE(1)

NAME
file - determine file type SYNOPSIS
file file ... DESCRIPTION
File performs a series of tests on each argument in an attempt to classify it. If an argument appears to be ascii, file examines the first 512 bytes and tries to guess its language. BUGS
It often makes mistakes. In particular it often suggests that command files are C programs. FILE(1)

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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 identified. 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 require- ments. 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 localized 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 identifies the file as a symbolic link. If -h is not specified 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 identifies 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-sensitive tests that are applied to a file in order to classify 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. " "$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_MES- SAGES, 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: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Availability |SUNWcsu | +-----------------------------+-----------------------------+ |CSI |enabled | +-----------------------------+-----------------------------+ |Interface Stability |Standard | +-----------------------------+-----------------------------+ SEE ALSO
elfdump(1), ls(1), magic(4), attributes(5), environ(5), largefile(5), standards(5) SunOS 5.10 16 July 2004 file(1)
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