SETGID
Section: POSIX Programmer's Manual (3P)
Updated: 2017
Page Index
PROLOG
This manual page is part of the POSIX Programmer's Manual.
The Linux implementation of this interface may differ (consult
the corresponding Linux manual page for details of Linux behavior),
or the interface may not be implemented on Linux.
NAME
setgid
--- set-group-ID
SYNOPSIS
#include <unistd.h>
int setgid(gid_t gid);
DESCRIPTION
If the process has appropriate privileges,
setgid()
shall set the real group ID, effective group ID, and the saved
set-group-ID of the calling process to
gid.
If the process does not have appropriate privileges, but
gid
is equal to the real group ID or the saved set-group-ID,
setgid()
shall set the effective group ID to
gid;
the real group ID and saved set-group-ID shall remain unchanged.
The
setgid()
function shall not affect the supplementary group list in any way.
Any supplementary group IDs of the calling process shall remain
unchanged.
RETURN VALUE
Upon successful completion, 0 is returned. Otherwise, -1 shall be
returned and
errno
set to indicate the error.
ERRORS
The
setgid()
function shall fail if:
- EINVAL
-
The value of the
gid
argument is invalid and is not supported by the implementation.
- EPERM
-
The process does not have appropriate privileges and
gid
does not match the real group ID or the saved set-group-ID.
The following sections are informative.
EXAMPLES
None.
APPLICATION USAGE
None.
RATIONALE
Refer to the RATIONALE section in
setuid().
FUTURE DIRECTIONS
None.
SEE ALSO
exec,
getegid(),
geteuid(),
getgid(),
getuid(),
setegid(),
seteuid(),
setregid(),
setreuid(),
setuid()
The Base Definitions volume of POSIX.1-2017,
<sys_types.h>,
<unistd.h>
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1-2017, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 7, 2018 Edition,
Copyright (C) 2018 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 .
Any typographical or formatting errors that appear
in this page are most likely
to have been introduced during the conversion of the source files to
man page format. To report such errors, see
https://www.kernel.org/doc/man-pages/reporting_bugs.html .