id man page

id — print real and effective user and group IDs

TL;DR

id -u

id -g

Synopsis

id [OPTION]... [USER]

Description

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

-a
ignore, for compatibility with other versions
-Z, --context
print only the security context of the process
-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
-z, --zero

delimit entries with NUL characters, not whitespace;

not permitted in default format

--help
display this help and exit
--version
output version information and exit

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

Author

Written by Arnold Robbins and David MacKenzie.

Reporting Bugs

GNU coreutils online help: <http://www.gnu.org/software/coreutils/>
Report id translation bugs to <http://translationproject.org/team/>

See Also

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

Referenced By

credentials(7), newgrp(1), qaxbase.3qt(3), sg(1).

November 2016 GNU coreutils 8.26 User Commands