$home/manuals/unix_v8/2/getuid

GETUID(2)                     System Calls Manual                    GETUID(2)



NAME
       getuid, getgid, geteuid, getegid, getpid, getppid - get user, group, or
       process identity

SYNOPSIS
       getuid()

       geteuid()

       getgid()

       getegid()

       getpid()

       getppid()

DESCRIPTION
       Getuid returns the real user ID of the current process, geteuid the ef‐
       fective  user ID.  The real user ID identifies the person who is logged
       in, in contradistinction to the effective user ID, which determines his
       access  permission  at the moment.  It is thus useful to programs which
       operate using the `set user ID' mode, to find out who invoked them.

       Getgid returns the real group ID, getegid the effective group ID.

       Getpid returns the process ID of the current process.  Most often it is
       used to generate uniquely-named temporary files.

       Getppid returns the process ID of the parent of the current process.

SEE ALSO
       setuid(2), mktemp(3), getlogin(3)



                                                                     GETUID(2)