1.\" $NetBSD: posix_openpt.3,v 1.3 2004/05/28 00:10:57 wiz Exp $ 2.\" 3.\" Copyright (c) 2004 The NetBSD Foundation, Inc. 4.\" All rights reserved. 5.\" 6.\" This code is derived from software contributed to The NetBSD Foundation 7.\" by Christos Zoulas. 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. All advertising materials mentioning features or use of this software 18.\" must display the following acknowledgement: 19.\" This product includes software developed by the NetBSD 20.\" Foundation, Inc. and its contributors. 21.\" 4. Neither the name of The NetBSD Foundation nor the names of its 22.\" contributors may be used to endorse or promote products derived 23.\" from this software without specific prior written permission. 24.\" 25.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 26.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 27.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 29.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35.\" POSSIBILITY OF SUCH DAMAGE. 36.\" 37.Dd May 25, 2004 38.Dt POSIX_OPENPT 3 39.Os 40.Sh NAME 41.Nm posix_openpt 42.Nd open a pseudo-terminal device 43.Sh LIBRARY 44.Lb libc 45.Sh SYNOPSIS 46.In stdlib.h 47.In fcntl.h 48.Ft int 49.Fn posix_openpt "int oflag" 50.Sh DESCRIPTION 51.Fn posix_openpt 52Searches for an unused master pseudo-terminal device, opens it, and returns 53a file descriptor associated the now used pseudo-terminal device. 54The 55.Fa oflag 56argument has the same meaning as in the 57.Xr open 2 58call. 59.Sh RETURN VALUES 60If successful, 61.Fn posix_openpt 62returns a non-negative integer, which corresponds to a file descriptor 63pointing to the master pseudo-terminal device. 64Otherwise, a value of \-1 is returned and 65.Va errno 66is set to indicate the error. 67.Sh SEE ALSO 68.Xr ioctl 2 , 69.Xr open 2 , 70.Xr grantpt 3 , 71.Xr ptsname 3 , 72.Xr unlockpt 3 73.Sh RATIONALE 74The standards committee did not want to directly expose the cloning device, 75thus decided to wrap the functionality in this function. 76The equivalent code would be: 77.Bd -literal 78 int 79 posix_openpt(int oflag) { 80 return open("/dev/ptmx", oflag); 81 } 82.Ed 83.Sh STANDARDS 84The 85.Fn posix_openpt 86function conforms to 87.St -p1003.1-2001 . 88