NAME    [Toc]    [Back]

     setregid - set real and effective group IDs

SYNOPSIS    [Toc]    [Back]

     #include <unistd.h>

     int
     setregid(gid_t rgid, gid_t egid);

DESCRIPTION    [Toc]    [Back]

     The real and effective group IDs of the current process  are
set according
     to  the  arguments.   If  the  real group ID is changed, the
saved group ID is
     changed to the new value of the effective group ID.

     Unprivileged users may change either group ID to the current
value of the
     real,  effective, or saved group ID.  Only the superuser may
make other
     changes.

     Supplying a value of -1 for either  the  real  or  effective
group ID forces
     the  system  to substitute the current ID in place of the -1
parameter.

     The setregid() function was intended to allow  swapping  the
real and effective
  group  IDs  in set-group-ID programs to temporarily
relinquish the
     set-group-ID value.  This purpose is now  better  served  by
the use of the
     setegid() function (see setuid(2)).

     When  setting  the  real and effective group IDs to the same
value, the
     setgid() function is preferred.

RETURN VALUES    [Toc]    [Back]

     Upon successful completion, a value of 0 is returned.   Otherwise, a value
     of -1 is returned and errno is set to indicate the error.

ERRORS    [Toc]    [Back]

     [EPERM]       The current process is not the superuser and a
change other
                   than changing the effective group  ID  to  the
real group ID
                   was specified.

SEE ALSO    [Toc]    [Back]

     getgid(2), setegid(2), setgid(2), setresgid(2), setuid(2)

STANDARDS    [Toc]    [Back]

     The setregid() function conforms to the IEEE Std 1003.1-2001
(``POSIX'')
     and X/Open Portability Guide Issue 4.3 (``XPG4.3'').  specifications.

     Note,   however,   that   prior   to  IEEE  Std  1003.1-2001
(``POSIX''), the
     setregid() function was not a part of the  IEEE  Std  1003.1
(``POSIX'')
     specification.   As  a  result, it may not be implemented on
all systems.

HISTORY    [Toc]    [Back]

     The setregid() function call appeared in 4.2BSD.  A semantically different
  version  appeared in 4.4BSD.  The current version, with
the original
     semantics restored, appeared in OpenBSD 3.3.

CAVEATS    [Toc]    [Back]

     The setregid() function  predates  POSIX  saved  group  IDs.
This implementation
  changes the saved group ID to the new value of the effective group
     ID if the real group ID is changed.   Other  implementations
may behave
     differently.

OpenBSD      3.6                         January     29,     2003