file

file linux command cheatsheet by Thamizhiniyan C S

Introduction

The man command is used to determine the file type.

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Syntax

file [-bcdEhiklLNnprsSvzZ0] [--apple] [--exclude-quiet] [--extension] [--mime-encoding] [--mime-type] [-e testname] [-F separator] [-f namefile] [-m magicfiles] [-P name=value] file ...

file -C [-m magicfiles]

file [--help]

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Important Flags

Flag	Description
--apple	Changes the command output to the one used by older versions of MacOS.
-b, --brief	Changes command output to brief mode.
-C, --compile	Creates an output file that contains a pre-parsed version of the magic file or directory.
-c, --checking-printout	Checks the printout for the parsed version of the magic file.
-d	Prints internal debugging information in the standard error format.
-E	On filesystem error, issues an error message and exits.
-e, --exclude	Excludes a test from the list of tests performed on a file.
--exclude-quiet	Excludes tests that the file command doesn't know about.
--extension	Prints a list of valid extensions for the file type.
-F, --separator	Uses the provided string as a separator between the file name and file type.
-f, --files-from	Uses a provided text file as a list of files to test. The list must contain only one file name per line.
-h, --no-deference	Disables following symbolic links.
-i, --mime	Changes the command output to a MIME-type string.
--mime-type, --mime-encoding	Changes the command output to a MIME-type string and only displays the specified element (type or encoding).
-k, --keep-going	Keeps the test going after the first results match.
-l, --list	Shows a list of matching patterns in descending order of strength.
-L, --deference	Enables following symbolic links.
-m, --magic-file	Uses an alternative magic file provided by the user.
-N, --no-pad	Doesn't pad the file names to align with the output.
-n, --no-buffer	Flushes the output after checking each file.
-p, --preserve-date	Attempts to preserve the last time the file was accessed to make it look like the file command didn't test it.
-P, --parameter	Sets various parameters, such as max bytes or recursion, count, and length limit.
-r, --raw	Disables translating unprintable characters.
-s, --special-files	Enables reading special files.
-S, --no-sandbox	Disables sandboxing on systems that support it.
-v, --version	Displays the version of the file command.
-z, --uncompress	Checks compressed files.
-Z, --uncompress-noreport	Checks compressed files and only displays file type without the compression.
-0, --print0	Displays a null character after the end of the file name.
--help	Displays the help message.

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Examples

Command	Description
file filename	To find the correct type of a file named 'filename'.
file [file name 1] [file name 2] … [file name n]	Test multiple files simultaneously.
file -b text.zip	View the file type in brief mode for a file named 'text.zip'.
file -b Example example.txt sample.png index.html	Display brief version of file type output.
file *	List each file type in the current directory.
file [path-to-directory]/*	List each file type inside a specific directory.
file -i filename	View the MIME file type of a file named 'filename'.
file -z filename	Check detailed information and content of a compressed file like ZIP or gzip.
file -z install.tar.gz	Test a compressed file to detect its content.
file -Z filename	Display only the file type of a compressed file like ZIP or gzip.
file -c filename	View the parsed version of a file, useful for debugging magic files.
file -c example.txt	Display the check printout for the parsed version of a file.
file [range1-range2]*	List all file types within specified Regex-style ranges.
file [a-l]*	Test files in a directory within the range of names from 'a' to 'l'.
file [a-z]* [A-Z]*	List all file types within specified Regex-style ranges.
file -f list.txt	Test files listed in a text file (one file per line).
file /dev/sda5	Test a special system file.
sudo file -s /dev/sda5	Fully test a special system file (requires root).
file -F + Example example.txt sample.png index.html	Define '+' as a separator between file name and type in output.
file -N Example example.txt sample.png index.html	Remove padding between file name and type in output.