NAME

       setregid - set real and effective group IDs

SYNOPSIS

       #include <unistd.h>

       int setregid(gid_t rgid, gid_t egid);

DESCRIPTION

       The setregid() function shall set the real and effective group IDs of the calling process.

       If  rgid is -1, the real group ID shall not be changed; if egid is -1, the effective group
       ID shall not be changed.

       The real and effective group IDs may be set to different values in the same call.

       Only a process with appropriate privileges can set the real group  ID  and  the  effective
       group ID to any valid value.

       A  non-privileged  process can set either the real group ID to the saved set-group-ID from
       one of the exec family of functions, or the effective group ID to the  saved  set-group-ID
       or the real group ID.

       Any supplementary group IDs of the calling process remain unchanged.

RETURN VALUE

       Upon successful completion, 0 shall be returned. Otherwise, -1 shall be returned and errno
       set to indicate the error, and neither of the group IDs are changed.

ERRORS

       The setregid() function shall fail if:

       EINVAL The value of the rgid or egid argument is invalid or out-of-range.

       EPERM  The process does not have appropriate privileges and a change other  than  changing
              the  real group ID to the saved set-group-ID, or changing the effective group ID to
              the real group ID or the saved set-group-ID, was requested.

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       If a set-group-ID process sets its effective group ID to its real group ID, it  can  still
       set its effective group ID back to the saved set-group-ID.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       exec()  , getegid() , geteuid() , getgid() , getuid() , setegid() , seteuid() , setgid() ,
       setreuid() , setuid() , the Base Definitions volume of IEEE Std 1003.1-2001, <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 .