xref: /openbsd-src/lib/libc/gen/getgrouplist.3 (revision b2ea75c1b17e1a9a339660e7ed45cd24946b230e)
1.\"	$OpenBSD: getgrouplist.3,v 1.8 2000/12/24 00:30:48 aaron Exp $
2.\"
3.\" Copyright (c) 1991, 1993
4.\"	The Regents of the University of California.  All rights reserved.
5.\"
6.\" Redistribution and use in source and binary forms, with or without
7.\" modification, are permitted provided that the following conditions
8.\" are met:
9.\" 1. Redistributions of source code must retain the above copyright
10.\"    notice, this list of conditions and the following disclaimer.
11.\" 2. Redistributions in binary form must reproduce the above copyright
12.\"    notice, this list of conditions and the following disclaimer in the
13.\"    documentation and/or other materials provided with the distribution.
14.\" 3. All advertising materials mentioning features or use of this software
15.\"    must display the following acknowledgement:
16.\"	This product includes software developed by the University of
17.\"	California, Berkeley and its contributors.
18.\" 4. Neither the name of the University nor the names of its contributors
19.\"    may be used to endorse or promote products derived from this software
20.\"    without specific prior written permission.
21.\"
22.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32.\" SUCH DAMAGE.
33.\"
34.Dd June 9, 1993
35.Dt GETGROUPLIST 3
36.Os
37.Sh NAME
38.Nm getgrouplist
39.Nd calculate group access list
40.Sh SYNOPSIS
41.Fd #include <unistd.h>
42.Ft int
43.Fn getgrouplist "const char *name" "gid_t basegid" "gid_t *groups" "int *ngroups"
44.Sh DESCRIPTION
45The
46.Fn getgrouplist
47function reads through the group file and calculates
48the group access list for the user specified in
49.Fa name .
50The
51.Fa basegid
52is automatically included in the groups list.
53Typically this value is given as
54the group number from the password file.
55.Pp
56The resulting group list is returned in the integer array pointed to by
57.Fa groups .
58The caller specifies the size of the
59.Fa groups
60array in the integer pointed to by
61.Fa ngroups ;
62the actual number of groups found is returned in
63.Fa ngroups .
64.Sh RETURN VALUES
65The
66.Fn getgrouplist
67function returns \-1 if the size of the group list is too small to
68hold all the user's groups.
69Here, the group array will be filled with as many groups as will fit.
70.Sh FILES
71.Bl -tag -width /etc/group -compact
72.It Pa /etc/group
73group database file
74.El
75.Sh SEE ALSO
76.Xr setgroups 2 ,
77.Xr initgroups 3
78.Sh HISTORY
79The
80.Fn getgrouplist
81function first appeared in
82.Bx 4.4 .
83.Sh BUGS
84The
85.Fn getgrouplist
86function uses the routines based on
87.Xr getgrent 3 .
88If the invoking program uses any of these routines,
89the group structure will be overwritten in the call to
90.Fn getgrouplist .
91