1.\" $NetBSD: getgroups.2,v 1.23 2013/07/14 14:29:09 njoly 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. Neither the name of the University nor the names of its contributors 15.\" may be used to endorse or promote products derived from this software 16.\" without specific prior written permission. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.\" @(#)getgroups.2 8.2 (Berkeley) 4/16/94 31.\" 32.Dd October 7, 2006 33.Dt GETGROUPS 2 34.Os 35.Sh NAME 36.Nm getgroups 37.Nd get group access list 38.Sh LIBRARY 39.Lb libc 40.Sh SYNOPSIS 41.In unistd.h 42.Ft int 43.Fn getgroups "int gidsetlen" "gid_t *gidset" 44.Sh DESCRIPTION 45.Fn getgroups 46gets the current group access list of the current user process 47and stores it in the array 48.Fa gidset . 49The parameter 50.Fa gidsetlen 51indicates the number of entries that may be placed in 52.Fa gidset . 53.Fn getgroups 54returns the actual number of groups returned in 55.Fa gidset . 56No more than 57.Brq Dv NGROUPS_MAX 58will ever 59be returned. 60If 61.Fa gidsetlen 62is 0, 63.Fn getgroups 64returns the number of groups without modifying the 65.Fa gidset 66array. 67.Pp 68This system call only returns the secondary groups. 69.Sh RETURN VALUES 70A successful call returns the number of groups in the group set. 71A value of \-1 indicates that an error occurred, and the error 72code is stored in the global variable 73.Va errno . 74.Sh ERRORS 75The possible errors for 76.Fn getgroups 77are: 78.Bl -tag -width Er 79.It Bq Er EINVAL 80The argument 81.Fa gidsetlen 82is non-zero and is smaller than the number of groups in the group set. 83.It Bq Er EFAULT 84The argument 85.Fa gidset 86specifies 87an invalid address. 88.El 89.Sh SEE ALSO 90.Xr getegid 2 , 91.Xr getgid 2 , 92.Xr setgroups 2 , 93.Xr initgroups 3 94.Sh STANDARDS 95The 96.Fn getgroups 97function conforms to 98.St -p1003.1-90 . 99.Sh HISTORY 100The 101.Fn getgroups 102function call appeared in 103.Bx 4.2 . 104