ID

id − print real and effective user and group IDs

id [OPTION]... [USERNAME]

Print user and group information for the specified USERNAME, or (when USERNAME omitted) for the current user.

−a

ignore, for compatibility with other versions

−Z, −−context

print only the security context of the current user

−g, −−group

print only the effective group ID

−G, −−groups

print all group IDs

−n, −−name

print a name instead of a number, for −ugG

−r, −−real

print the real ID instead of the effective ID, with −ugG

−u, −−user

print only the effective user ID

−−help

display this help and exit

−−version

output version information and exit

Without any OPTION, print some useful set of identified information.

Written by Arnold Robbins and David MacKenzie.

Report id bugs to bug−coreutils@gnu.org
GNU coreutils home page: <http://www.gnu.org/software/coreutils/>
General help using GNU software: <http://www.gnu.org/gethelp/>
Report id translation bugs to <http://translationproject.org/team/>

Copyright © 2010 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.

The full documentation for id is maintained as a Texinfo manual. If the info and id programs are properly installed at your site, the command

info coreutils 'id invocation'

should give you access to the complete manual.