1.\" $NetBSD: getgroups.2,v 1.16 2002/04/29 01:41:45 simonb 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.\" @(#)getgroups.2 8.2 (Berkeley) 4/16/94 35.\" 36.Dd April 16, 1994 37.Dt GETGROUPS 2 38.Os 39.Sh NAME 40.Nm getgroups 41.Nd get group access list 42.Sh LIBRARY 43.Lb libc 44.Sh SYNOPSIS 45.Fd #include \*[Lt]unistd.h\*[Gt] 46.Ft int 47.Fn getgroups "int gidsetlen" "gid_t *gidset" 48.Sh DESCRIPTION 49.Fn getgroups 50gets the current group access list of the current user process 51and stores it in the array 52.Fa gidset . 53The parameter 54.Fa gidsetlen 55indicates the number of entries that may be placed in 56.Fa gidset . 57.Fn getgroups 58returns the actual number of groups returned in 59.Fa gidset . 60No more than 61.Dv {NGROUPS_MAX} 62will ever 63be returned. 64If 65.Fa gidsetlen 66is 0, 67.Fn getgroups 68returns the number of groups without modifying the 69.Fa gidset 70array. 71.Sh RETURN VALUES 72A successful call returns the number of groups in the group set. 73A value of -1 indicates that an error occurred, and the error 74code is stored in the global variable 75.Va errno . 76.Sh ERRORS 77The possible errors for 78.Fn getgroups 79are: 80.Bl -tag -width Er 81.It Bq Er EINVAL 82The argument 83.Fa gidsetlen 84is non-zero and is smaller than the number of groups in the group set. 85.It Bq Er EFAULT 86The argument 87.Fa gidset 88specifies 89an invalid address. 90.El 91.Sh SEE ALSO 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