print the user name and ID, and group name and ID
id-G [-n] [user]
id-g [-nr] [user]
id-u [-nr] [user]
id displays information on the calling process's user and group
If user is specified, then information on the
user login is displayed instead.
The information displayed is the user ID and name and the group
ID and name.
If the real and effective user IDs do not
match, both are printed.
The same is true for real and effective group
IDs. If the user belongs to more than one group, the extra groups
are also displayed.
The output format is a sequence of equality statements of the form
each separated by a
The numeric-id is the numeric
representation of the group or user, real or effective ID.
The name is the symbolic representation of this ID
(the login name of the user, for example).
In the C locale, the id-title is
one of the following strings.
effective user ID
effective group ID
supplementary group IDs
The equality statements are presented in the order given in the table,
with each statement present according to the conditions explained in
the first paragraph.
However, the groups statement, which is
always written last, if at all, is slightly different because each
extra supplementary group after the first does not have its own
equality statement but adds
to the end of the output line.
This option does nothing.
It is for backward compatibility only,
and should not be used.
Display all different (numeric) group IDs (real, effective, and
supplementary), each separated by a space.
Display only the effective (numeric) group ID.
Display the name instead of the numeric ID (when used with
-G, -g, or %-u).
Display the real ID instead of the effective ID (when used
with -g or -u).
Display only the effective (numeric) user ID.
language-specific message file (See LANG on