ID(1)                       General Commands Manual                      ID(1)

NAME
     id – return user identity

SYNOPSIS
     id [user]
     id -A
     id -F [user]
     id -G [-n] [user]
     id -P [user]
     id -g [-nr] [user]
     id -p [user]
     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
     displayed.

     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:

     -A      Display the process audit user ID and other process audit
             properties, which requires privilege.

     -F      Display the full name of the user.

     -G      Display the different group IDs (effective, real and
             supplementary) as white-space separated numbers, in no particular
             order.

     -P      Display the id as a password file entry.

     -a      Ignored for compatibility with other id implementations.

     -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
             displayed as a name, preceded by the keyword “rgid”.  The list of
             groups to which the user belongs is then displayed as names,
             preceded 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
             effective ID.

     -u      Display the effective user ID as a number.

EXIT STATUS
     The id utility exits 0 on success, and >0 if an error occurs.

EXAMPLES
     Show information for the user ‘bob’ as a password file entry:

           $ id -P bob
           bob:*:0:0::0:0:Robert:/bob:/usr/local/bin/bash

     Same output as groups(1) for the root user:

           $ id -Gn root
           wheel operator

     Show human readable information about ‘alice’:

           $ id -p alice
           uid     alice
           groups  alice webcamd vboxusers

     Assuming the user ‘bob’ executed “su -l” to simulate a root login,
     compare the result of the following commands:

           # id -un
           root
           # who am i
           bob          pts/5        Dec  4 19:51

SEE ALSO
     groups(1), who(1)

STANDARDS
     The id function is expected to conform to IEEE Std 1003.2 (“POSIX.2”).

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 appeared in 4.4BSD.

macOS 15.2                       March 5, 2011                      macOS 15.2