v7 man page for getuid

GETUID(2)							System Calls Manual							 GETUID(2)

NAME
       getuid, getgid, geteuid, getegid - get user and group identity

SYNOPSIS
       getuid( )

       geteuid( )

       getgid( )

       getegid( )

DESCRIPTION
       Getuid  returns	the  real  user  ID  of the current process, geteuid the effective 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  pro-
       grams 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.

SEE ALSO
       setuid(2)

ASSEMBLER
       (getuid = 24.)
       sys getuid
       (real user ID in r0, effective user ID in r1)

       (getgid = 47.)
       sys getgid
       (real group ID in r0, effective group ID in r1)

																	 GETUID(2)