'\" te
.\" Copyright (c) 2004, Sun Microsystems, Inc.  All Rights Reserved.
.TH setregid 2 "22 Mar 2004" "SunOS 5.11" "System Calls"
.SH NAME
setregid \- set real and effective group IDs
.SH SYNOPSIS
.LP
.nf
#include <unistd.h>

\fBint\fR \fBsetregid\fR(\fBgid_t\fR \fIrgid\fR, \fBgid_t\fR \fIegid\fR);
.fi

.SH DESCRIPTION
.sp
.LP
The \fBsetregid()\fR function is used to set the real and effective group IDs of the calling process.  If \fIrgid\fR is \(mi1, the real group ID is not changed; if \fIegid\fR is \(mi1, the effective group ID is not changed.  The real and effective group IDs may be set to different values in the same call.
.sp
.LP
If the {\fBPRIV_PROC_SETID\fR} privilege is asserted in the effective set of the calling process, the real group ID and the effective group ID can be set to any legal value.
.sp
.LP
If the {\fBPRIV_PROC_SETID\fR} privilege is not asserted in the effective set of the calling process, either the real group ID can be set to the saved set-group-ID from \fBexecve\fR(2), or the effective group ID can either be set to the saved set-group-ID or the real group ID.
.sp
.LP
In either case, if the real group ID is being changed (that is, if \fIrgid\fR is not \(mi1), or the effective group ID is being changed to a value not equal to the real group ID, the saved set-group-ID is set equal to the new effective group ID.
.SH RETURN VALUES
.sp
.LP
Upon successful completion, 0 is returned. Otherwise, \(mi1 is returned, \fBerrno\fR is set to indicate the error, and neither of the group IDs will be changed.
.SH ERRORS
.sp
.LP
The \fBsetregid()\fR function will fail if:
.sp
.ne 2
.mk
.na
\fB\fBEINVAL\fR\fR
.ad
.RS 10n
.rt  
The value of \fIrgid\fR or \fIegid\fR is less than 0 or greater than \fBUID_MAX\fR (defined in <\fBlimits.h\fR>).
.RE

.sp
.ne 2
.mk
.na
\fB\fBEPERM\fR\fR
.ad
.RS 10n
.rt  
The {\fBPRIV_PROC_SETID\fR} privilege is not asserted in the effective set of the calling processes and a change was specified other than changing the real group \fBID\fR to the saved set-group-\fBID\fR or changing the effective group \fBID\fR to the real group \fBID\fR or the saved group ID.
.RE

.SH USAGE
.sp
.LP
If a set-group-\fBID\fR process sets its effective group \fBID\fR to its real group \fBID\fR, it can still set its effective group \fBID\fR back to the saved set-group-\fBID\fR.
.SH ATTRIBUTES
.sp
.LP
See \fBattributes\fR(5) for descriptions of the following attributes:
.sp

.sp
.TS
tab() box;
cw(2.75i) |cw(2.75i) 
lw(2.75i) |lw(2.75i) 
.
ATTRIBUTE TYPEATTRIBUTE VALUE
_
Interface StabilityCommitted
_
StandardSee \fBstandards\fR(5).
.TE

.SH SEE ALSO
.sp
.LP
\fBexecve\fR(2), \fBgetgid\fR(2), \fBsetreuid\fR(2), \fBsetuid\fR(2), \fBattributes\fR(5), \fBprivileges\fR(5), \fBstandards\fR(5)