chown [OPTION]... OWNER[:[GROUP]] FILE... chown [OPTION]... :GROUP FILE... chown [OPTION]... --reference=RFILE FILE...
chown is as specified in the Single UNIX Specification but with differences as listed below.
The use of the '.' character as a separator between the specification of the user name and group name is supported (in addition to the use of the ':' character as specified in the Single UNIX Specification).
The behaviors specified in this section are expected to disappear from a future version of the LSB; applications should only use the non-LSB-deprecated behaviors.
is like verbose, but reports only when a change is made.
affects the referent of each symbolic link, rather than the symbolic link itself.
affects symbolic links instead of any referenced file. (Available only on systems that can change the ownership of a symlink.)
changes 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.
suppresses most error messages.
uses RFILE's owner and group rather than the specified OWNER:GROUP values.
outputs a diagnostic for every file processed.
outputs version information and exits.