Usage: /usr/bin/id [OPTION]... [USER]... Print user and group information for each specified USER, or (when USER omitted) for the current process. -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 -u, -g, -G -r, --real print the real ID instead of the effective ID, with -u, -g, -G -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. Report bugs to: . GNU coreutils home page: General help using GNU software: Full documentation or available locally via: info '(coreutils) id invocation'