$ chown --help
Usage: chown [OPTION]... [OWNER][:[GROUP]] FILE...
or: chown [OPTION]... --reference=RFILE FILE...
Change the owner and/or group of each FILE to OWNER and/or GROUP.
With --reference, change the owner and group of each FILE to those 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)
change the owner and/or group of each file only if
its current owner and/or group match those specified
here. Either may be omitted, in which case a match
is not required for the omitted attribute
--no-preserve-root do not treat '/' specially (the default)
--preserve-root fail to operate recursively on '/'
--reference=RFILE use RFILE's owner and group rather than
specifying OWNER:GROUP values
-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
-P do not traverse any symbolic links (default)
--help display this help and exit
--version output version information and exit
Owner is unchanged if missing. Group is unchanged if missing, but changed
to login group if implied by a ':' following a symbolic OWNER.
OWNER and GROUP may be numeric as well as symbolic.
chown root /u Change the owner of /u to "root".
chown root:staff /u Likewise, but also change its group to "staff".
chown -hR root /u Change the owner of /u and subfiles to "root".
GNU coreutils online help: <http://www.gnu.org/software/coreutils/>
Full documentation at: <http://www.gnu.org/software/coreutils/chown>
or available locally via: info '(coreutils) chown invocation'