chgrp --version (return code: 0)
chgrp (GNU coreutils) 8.25 Copyright (C) 2016 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Written by David MacKenzie and Jim Meyering.
chgrp --help (return code: 0)
Usage: chgrp [OPTION]... GROUP FILE... or: 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 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 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 Examples: chgrp staff /u Change the group of /u to "staff". chgrp -hR staff /u Change the group of /u and subfiles to "staff". GNU coreutils online help: <http://www.gnu.org/software/coreutils/> Full documentation at: <http://www.gnu.org/software/coreutils/chgrp> or available locally via: info '(coreutils) chgrp invocation'