DOKK / manpages / debian 12 / manpages-dev / getegid.2.en
getgid(2) System Calls Manual getgid(2)

getgid, getegid - get group identity

Standard C library (libc, -lc)

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

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

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

These functions are always successful and never modify errno.

POSIX.1-2001, POSIX.1-2008, 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.

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.

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

2022-10-30 Linux man-pages 6.03