1.\" $NetBSD: getusershell.3,v 1.6 1999/03/22 19:44:42 garbled Exp $ 2.\" 3.\" Copyright (c) 1985, 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.\" @(#)getusershell.3 8.1 (Berkeley) 6/4/93 31.\" $FreeBSD: src/lib/libc/gen/getusershell.3,v 1.12 2007/01/09 00:27:54 imp Exp $ 32.\" 33.Dd May 5, 2019 34.Dt GETUSERSHELL 3 35.Os 36.Sh NAME 37.Nm getusershell , 38.Nm setusershell , 39.Nm endusershell 40.Nd get valid user shells 41.Sh LIBRARY 42.Lb libc 43.Sh SYNOPSIS 44.In unistd.h 45.Ft char * 46.Fn getusershell void 47.Ft void 48.Fn setusershell void 49.Ft void 50.Fn endusershell void 51.Sh DESCRIPTION 52The 53.Fn getusershell 54function 55returns a pointer to a valid user shell as defined by the 56system manager in the shells database as described in 57.Xr shells 5 . 58If the shells database is not available, 59.Fn getusershell 60behaves as if 61.Pa /bin/sh 62and 63.Pa /bin/csh 64were listed. 65.Pp 66The 67.Fn getusershell 68function 69reads the next 70line (opening the file if necessary); 71.Fn setusershell 72rewinds the file; 73.Fn endusershell 74closes it. 75.Sh RETURN VALUES 76The 77.Fn getusershell 78function returns 79.Dv NULL 80on 81.Dv EOF . 82.Sh FILES 83.Bl -tag -width /etc/shells -compact 84.It Pa /etc/shells 85.El 86.Sh SEE ALSO 87.Xr nsswitch.conf 5 , 88.Xr shells 5 89.Sh HISTORY 90The 91.Fn getusershell 92function appeared in 93.Bx 4.3 . 94.Sh BUGS 95The 96.Fn getusershell 97function leaves its result in an internal static object and returns 98a pointer to that object. 99Subsequent calls to 100.Fn getusershell 101will modify the same object. 102