1.\" $NetBSD: getgrouplist.3,v 1.13 2005/01/06 15:29:35 lukem Exp $ 2.\" 3.\" Copyright (c) 2005 The NetBSD Foundation, Inc. 4.\" All rights reserved. 5.\" 6.\" This code is derived from software contributed to The NetBSD Foundation 7.\" by Luke Mewburn. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 3. 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Redistributions in binary form must reproduce the above copyright 46.\" notice, this list of conditions and the following disclaimer in the 47.\" documentation and/or other materials provided with the distribution. 48.\" 3. Neither the name of the University nor the names of its contributors 49.\" may be used to endorse or promote products derived from this software 50.\" without specific prior written permission. 51.\" 52.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 53.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 54.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 55.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 56.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 57.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 58.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 59.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 60.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 61.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 62.\" SUCH DAMAGE. 63.\" 64.\" @(#)getgrouplist.3 8.1 (Berkeley) 6/9/93 65.\" 66.Dd January 6, 2005 67.Dt GETGROUPLIST 3 68.Os 69.Sh NAME 70.Nm getgrouplist , 71.Nm getgroupmembership , 72.Nd calculate group access list 73.Sh LIBRARY 74.Lb libc 75.Sh SYNOPSIS 76.In unistd.h 77.Ft int 78.Fn getgrouplist "const char *name" "gid_t basegid" "gid_t *groups" "int *ngroups" 79.Ft int 80.Fn getgroupmembership "const char *name" "gid_t basegid" "gid_t *groups" "int maxgrp" "int *ngroups" 81.Sh DESCRIPTION 82The 83.Fn getgrouplist 84and 85.Fn getgroupmembership 86functions read through the group database and calculate 87the group access list for the user specified in 88.Fa name . 89The 90.Fa basegid 91is automatically included in the groups list. 92Typically this value is given as 93the group number from the password database. 94.Pp 95The resulting group list is returned in the integer array pointed to by 96.Fa groups . 97.Pp 98For 99.Fn getgrouplist , 100the caller specifies the size of the 101.Fa groups 102array in the integer pointed to by 103.Fa ngroups . 104.Pp 105For 106.Fn getgroupmembership , 107the caller specifies the size of the 108.Fa groups 109array in 110.Fa maxgrp . 111.Pp 112The actual number of groups found is returned in 113.Fa ngroups . 114.Pp 115Duplicate group ids will be suppressed from the result. 116.Sh RETURN VALUES 117The 118.Fn getgrouplist 119and 120.Fn getgroupmembership 121functions 122return 0 if successful, and 123return \-1 if the size of the group list is too small to 124hold all the user's groups. 125In the latter case, the 126.Fa groups 127array will be filled with as many groups as will fit and 128.Fa ngroups 129will contain the total number of groups found. 130.Sh FILES 131.Bl -tag -width /etc/group -compact 132.It Pa /etc/group 133group membership list 134.El 135.Sh SEE ALSO 136.Xr setgroups 2 , 137.Xr initgroups 3 , 138.Xr group 5 139.Sh HISTORY 140The 141.Fn getgrouplist 142function first appeared in 143.Bx 4.4 . 144The 145.Fn getgroupmembership 146function first appeared in 147.Nx 3.0 148to address an API deficiency in 149.Fn getgrouplist . 150.Sh BUGS 151The 152.Fn getgrouplist 153function 154uses the routines based on 155.Xr getgrent 3 . 156If the invoking program uses any of these routines, 157the group structure will 158be overwritten in the call to 159.Fn getgrouplist . 160