2004-11-03 13:51:07 +00:00
|
|
|
.\" Copyright (C), 1994, Graeme W. Wilford. (Wilf.)
|
|
|
|
.\"
|
|
|
|
.\" Permission is granted to make and distribute verbatim copies of this
|
|
|
|
.\" manual provided the copyright notice and this permission notice are
|
|
|
|
.\" preserved on all copies.
|
|
|
|
.\"
|
|
|
|
.\" Permission is granted to copy and distribute modified versions of this
|
|
|
|
.\" manual under the conditions for verbatim copying, provided that the
|
|
|
|
.\" entire resulting derived work is distributed under the terms of a
|
|
|
|
.\" permission notice identical to this one.
|
|
|
|
.\"
|
|
|
|
.\" Since the Linux kernel and libraries are constantly changing, this
|
|
|
|
.\" manual page may be incorrect or out-of-date. The author(s) assume no
|
|
|
|
.\" responsibility for errors or omissions, or for damages resulting from
|
|
|
|
.\" the use of the information contained herein. The author(s) may not
|
|
|
|
.\" have taken the same level of care in the production of this manual,
|
|
|
|
.\" which is licensed free of charge, as they might when working
|
|
|
|
.\" professionally.
|
|
|
|
.\"
|
|
|
|
.\" Formatted or processed versions of this manual, if unaccompanied by
|
|
|
|
.\" the source, must acknowledge the copyright and authors of this work.
|
|
|
|
.\"
|
|
|
|
.\" Fri Jul 29th 12:56:44 BST 1994 Wilf. <G.Wilford@ee.surrey.ac.uk>
|
|
|
|
.\" Modified 1997-01-31 by Eric S. Raymond <esr@thyrsus.com>
|
|
|
|
.\" Modified 2002-03-09 by aeb
|
|
|
|
.\"
|
|
|
|
.TH SETGID 2 2002-03-09 "Linux 2.5" "Linux Programmer's Manual"
|
|
|
|
.SH NAME
|
|
|
|
setgid \- set group identity
|
|
|
|
.SH SYNOPSIS
|
|
|
|
.B #include <sys/types.h>
|
|
|
|
.br
|
|
|
|
.B #include <unistd.h>
|
|
|
|
.sp
|
|
|
|
.BI "int setgid(gid_t " gid );
|
|
|
|
.SH DESCRIPTION
|
|
|
|
.B setgid
|
|
|
|
sets the effective group ID of the current process. If the caller is the
|
|
|
|
superuser, the real and saved group ID's are also set.
|
|
|
|
|
|
|
|
Under Linux,
|
|
|
|
.B setgid
|
|
|
|
is implemented like the POSIX version with the _POSIX_SAVED_IDS feature.
|
|
|
|
This allows a setgid program that is not suid root to drop all of its group
|
|
|
|
privileges, do some un-privileged work, and then re-engage the original
|
|
|
|
effective group ID in a secure manner.
|
|
|
|
.SH "RETURN VALUE"
|
|
|
|
On success, zero is returned. On error, \-1 is returned, and
|
|
|
|
.I errno
|
|
|
|
is set appropriately.
|
|
|
|
.SH ERRORS
|
|
|
|
.TP
|
|
|
|
.B EPERM
|
2004-11-10 18:17:26 +00:00
|
|
|
The user is not the superuser (does not have the CAP_SETGID capability), and
|
2004-11-03 13:51:07 +00:00
|
|
|
.I gid
|
|
|
|
does not match the effective group ID or saved set-group-ID of
|
|
|
|
the calling process.
|
|
|
|
.SH "CONFORMING TO"
|
|
|
|
SVr4, SVID.
|
|
|
|
.SH "SEE ALSO"
|
|
|
|
.BR getgid (2),
|
|
|
|
.BR setegid (2),
|
|
|
|
.BR setregid (2),
|
|
|
|
.BR capabilities (7)
|