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NAME
getgid, getegid — get group process identification
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <sys/types.h>
#include <unistd.h>
gid_t
getgid(void);
gid_t
getegid(void);
DESCRIPTION
The getgid() system call returns the real group ID of the calling process, getegid() returns the
effective group ID of the calling process.
The real group ID is specified at login time.
The real group ID is the group of the user who invoked the program. As the effective group ID gives the
process additional permissions during the execution of “set-group-ID” mode processes, getgid() is used to
determine the real-user-id of the calling process.
ERRORS
The getgid() and getegid() system calls are always successful, and no return value is reserved to
indicate an error.
SEE ALSO
getuid(2), issetugid(2), setgid(2), setregid(2)
STANDARDS
The getgid() and getegid() system calls are expected to conform to ISO/IEC 9945-1:1990 (“POSIX.1”).
Debian June 4, 1993 GETGID(2)