NAME

getuid, geteuid, getgid, getegid - get real user, effective user, real group, and effective group IDs

SYNOPSIS

#include <sys/types.h>

#include <unistd.h>
uid_t getuid(void);
uid_t geteuid(void);
gid_t getgid(void);
gid_t getegid(void);

MT-LEVEL

Async-Signal-Safe

DESCRIPTION

getuid( ) returns the real user ID of the calling process. The real user ID identifies the person who is logged in.

geteuid( ) returns the effective user ID of the calling process. The effective user ID gives the process various permissions during execution of ``set-user-ID ''mode processes which use getuid ( ) to determine the real user ID of the process that invoked them.

getgid( ) returns the real group ID of the calling process.

getegid( ) returns the effective group ID of the calling process.

SEE ALSO

intro(2), setuid(2)