1.\" $OpenBSD: initgroups.3,v 1.10 2000/12/24 00:30:49 aaron Exp $ 2.\" 3.\" Copyright (c) 1983, 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 4, 1993 35.Dt INITGROUPS 3 36.Os 37.Sh NAME 38.Nm initgroups 39.Nd initialize supplementary group IDs 40.Sh SYNOPSIS 41.Fd #include <unistd.h> 42.Ft int 43.Fn initgroups "const char *name" "gid_t basegid" 44.Sh DESCRIPTION 45The 46.Fn initgroups 47function uses the 48.Xr getgrouplist 3 49function to calculate the supplementary group IDs for the user specified in 50.Fa name . 51This group list then set up for the current process using 52.Xr setgroups 2 . 53The 54.Fa basegid 55is automatically included in the group list. 56Typically this value is given as the group number from the password file. 57.Pp 58If the groups database lists more than 59.Ev NGROUPS 60groups for 61.Fa name 62(including one for 63.Fa basegid ) , 64the later groups are ignored. 65.Sh RETURN VALUES 66The 67.Fn initgroups 68function returns \-1 if it was not invoked by the superuser. 69.Sh SEE ALSO 70.Xr setgroups 2 , 71.Xr getgrouplist 3 72.Sh HISTORY 73The 74.Fn initgroups 75function appeared in 76.Bx 4.2 . 77.Sh BUGS 78The 79.Xr getgrouplist 3 80function called by 81.Fn initgroups 82uses the routines based on 83.Xr getgrent 3 . 84If the invoking program uses any of these routines, the group structure 85will be overwritten in the call to 86.Fn initgroups . 87