trusty (3) setregid.3posix.gz

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 .