chgrp - change group ownership

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

Change the group of each FILE to GROUP. With --reference, change the group of each FILE to that of RFILE.

-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 referent of each symbolic link (this is the default), rather than the symbolic link itself

-h, --no-dereference

affect symbolic links instead of any referenced file (useful only on systems that can change the ownership of a symlink)

--no-preserve-root

do not treat '/' specially (the default)

--preserve-root

fail to operate recursively on '/'

--reference=RFILE

use RFILE's group rather than specifying a GROUP. RFILE is always dereferenced if a symbolic link.

-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 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 encountered

-P

do not traverse any symbolic links (default)

--help

display this help and exit

--version

output version information and exit

chgrp staff /u

Change the group of /u to "staff".

chgrp -hR staff /u

Change the group of /u and subfiles to "staff".

chown(1), chown(2)

Full documentation <https://www.gnu.org/software/coreutils/chgrp>
or available locally via: info '(coreutils) chgrp invocation'