getgid(2)

NAME
getgid, getegid - get group identity

LIBRARY
Standard C library (libc, -lc)

SYNOPSIS
#include <unistd.h>

gid_t getgid(void);
gid_t getegid(void);

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

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

ERRORS
These functions are always successful and never modify errno.

VERSIONS
On Alpha, instead of a pair of getgid() and getegid() system calls, a single getxgid() system call is provided, which returns a pair of real and effective GIDs. The glibc getgid() and getegid() wrapper functions transparently deal with this. See syscall(2) for details regarding register mapping.

STANDARDS
POSIX.1-2024.

HISTORY
POSIX.1-2001, 4.3BSD.

The original Linux getgid() and getegid() system calls supported only 16-bit group IDs. Subsequently, Linux 2.4 added getgid32() and getegid32(), supporting 32-bit IDs. The glibc getgid() and getegid() wrapper functions transparently deal with the variations across kernel versions.

SEE ALSO
getresgid(2), setgid(2), setregid(2), credentials(7)