NAME

       setgid - set-group-ID

SYNOPSIS

       #include <unistd.h>

       int setgid(gid_t gid);

DESCRIPTION

       If the process has appropriate privileges, setgid() shall set the real group ID, effective
       group ID, and the saved set-group-ID of the calling process to gid.

       If the process does not have appropriate privileges, but gid is equal to the real group ID
       or  the  saved  set-group-ID,  setgid()  shall set the effective group ID to gid; the real
       group ID and saved set-group-ID shall remain unchanged.

       The setgid() function shall not affect the supplementary group list in any way.

       Any supplementary group IDs of the calling process shall remain unchanged.

RETURN VALUE

       Upon successful completion, 0 is returned. Otherwise, -1 shall be returned and  errno  set
       to indicate the error.

ERRORS

       The setgid() function shall fail if:

       EINVAL The   value   of  the  gid  argument  is  invalid  and  is  not  supported  by  the
              implementation.

       EPERM  The process does not have appropriate privileges and gid does not  match  the  real
              group ID or the saved set-group-ID.

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       None.

RATIONALE

       Refer to the RATIONALE section in setuid() .

FUTURE DIRECTIONS

       None.

SEE ALSO

       exec()  , getegid() , geteuid() , getgid() , getuid() , setegid() , seteuid() , setregid()
       ,  setreuid()  ,  setuid()  ,  the  Base  Definitions  volume   of   IEEE Std 1003.1-2001,
       <sys/types.h>, <unistd.h>

COPYRIGHT

       Portions  of  this  text  are  reprinted  and  reproduced in electronic form from IEEE Std
       1003.1, 2003 Edition, Standard for Information Technology  --  Portable  Operating  System
       Interface  (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by
       the Institute of Electrical and Electronics Engineers, Inc and  The  Open  Group.  In  the
       event  of  any  discrepancy  between this version and the original IEEE and The Open Group
       Standard, the original IEEE and The Open Group  Standard  is  the  referee  document.  The
       original Standard can be obtained online at http://www.opengroup.org/unix/online.html .