ID(1) MachTen Reference Manual ID(1)
NAME
id - return user identity
SYNOPSIS
id [user]
id -G [-n] [user]
id -g [-nr] [user]
id -p
id -u [-nr] [user]
DESCRIPTION
The id utility displays the user and group names and numeric
IDs, of the
calling process, to the standard output. If the real and
effective IDs
are different, both are displayed, otherwise only the real
ID is dis-
played.
If a user (login name or user
ID) is specified, the user and group IDs of
that user are displayed. In this case, the real and
effective IDs are
assumed to be the same.
The options are as follows:
-G Display the different group
IDs (effective, real and supplemen-
tary) as white-space separated numbers, in no particular
order.
-g Display the effective group ID as a number.
-n Display the name of the user
or group ID for the -G, -g and -u
options instead of the number. If any of the ID numbers
cannot
be mapped into names, the number will be displayed as
usual.
-p Make the output
human-readable. If the user name returned by
getlogin(2) is different from the login name referenced by
the
user ID, the name returned by getlogin(2) is displayed,
preceded
by the keyword ‘‘login’’. The user
ID as a name is displayed,
preceded by the keyword ‘‘uid’’. If
the effective user ID is
different from the real user ID, the real user ID is
displayed as
a name, preceded by the keyword
‘‘euid’’. If the effective group
ID is different from the real group ID, the real group ID is
dis-
played as a name, preceded by the keyword
‘‘rgid’’. The list of
groups to which the user belongs is then displayed as names,
pre-
ceded by the keyword ‘‘groups’’.
Each display is on a separate
line.
-r Display the real ID for the
-g and -u options instead of the ef-
fective ID.
-u Display the effective user ID as a number.
The id utility exits 0 on success, and >0 if an error occurs.
SEE ALSO
who(1)
STANDARDS
The id function is expected to conform to IEEE Std1003.2
(‘‘POSIX’’).
HISTORY
The historic groups(1) command is equivalent to
‘‘id -Gn [user]’’.
The historic whoami(1) command is equivalent to ‘‘id -un’’.
The id command appears in 4.4BSD.
4.4BSD July 25, 1995 2