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chgrp linux command

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Changes group ownership of a file or files.
Change the group of each FILE to GROUP. With --reference, change the group of each FILE to that of RFILE.

chgrp syntax
chgrp [OPTION]... GROUP FILE...
chgrp [OPTION]... --reference=RFILE FILE...

Options
-c, --changes
Like verbose but report only when a change is made.
-f, --silent, --quiet
Suppress most error messages.
-v, --verbose
Output a diagnostic for every file processed.
--dereference
Affect the referenced file of each symbolic link, rather than the symbolic link itself, which is default setting.
-h, --no-dereference
Affect symbolic links instead of any referenced file. This option is useful only on systems that can change the ownership of a symlink.
--no-preserve-root
Do not treat '/' in any special way. This option is the default.
--preserve-root
Do not operate recursively on '/'.
--reference=RFILE
Use RFILE's group rather than specifying a GROUP value.
-R, --recursive
Operate on files and directories recursively.
 

The following options modify how a hierarchy is traversed when the -R option is also specified. If more than one of these options is specified, only the final one takes effect:
-H
If a command line argument is a symbolic link to a directory, traverse it.
-L
Traverse every symbolic link to a directory.
-P
Do not traverse any symbolic links. This option is the default.
--help
Display a help message and exit.
--version
Output version information and exit.
 
chgrp examples
chgrp hope file.txt

Change the owning group of the file file.txt to the group named hope.
chgrp -hR staff /office/files

Change the owning group of /office/files, and all subdirectories, to the group staff.

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