Unknown option: "-2" Unix manual page for getgid. (host=minya system=Darwin)
GETGID(2)                   BSD System Calls Manual                  GETGID(2)

NAME
     getegid, getgid -- get group process identification

SYNOPSIS
     #include <unistd.h>

     gid_t
     getegid(void);

     gid_t
     getgid(void);

DESCRIPTION
     The getgid() function 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() functions are always successful; no return
     value is reserved to indicate an error.

LEGACY SYNOPSIS
     #include <sys/types.h>
     #include <unistd.h>

     The include file <sys/types.h> is necessary.

SEE ALSO
     getuid(2), setregid(2), setgid(3)

STANDARDS
     getgid() and getegid() conform to IEEE Std 1003.1-1988 (``POSIX.1'').

4.2 Berkeley Distribution        June 4, 1993        4.2 Berkeley Distribution