1.\" $NetBSD: unlockpt.3,v 1.4 2008/04/30 13:10:51 martin 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.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 19.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 20.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 21.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 22.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 23.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 24.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 25.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 26.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 27.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 28.\" POSSIBILITY OF SUCH DAMAGE. 29.\" 30.Dd May 25, 2004 31.Dt UNLOCKPT 3 32.Os 33.Sh NAME 34.Nm unlockpt 35.Nd unlock the slave pseudo-terminal device 36.Sh LIBRARY 37.Lb libc 38.Sh SYNOPSIS 39.In stdlib.h 40.Ft int 41.Fn unlockpt "int fildes" 42.Sh DESCRIPTION 43The 44.Fn unlockpt 45unlocks access to the pseudo-terminal device corresponding to the 46master pseudo-terminal device associated with 47.Fa fildes . 48Conforming applications must call this function before opening the 49slave pseudo-terminal device. 50.Sh RETURN VALUES 51If successful, 52.Fn unlockpt 53returns 0; otherwise a value of \-1 is returned and 54.Va errno 55is set to indicate the error. 56.Sh ERRORS 57The 58.Fn unlockpt 59function will fail if: 60.Bl -tag -width Er 61.It Bq Er EACCESS 62the corresponding pseudo-terminal device could not be accessed. 63.It Bq Er EBADF 64.Fa fildes 65is not a valid descriptor. 66.It Bq Er EINVAL 67.Fa fildes 68is not associated with a master pseudo-terminal device. 69.El 70.Sh NOTES 71In 72.Nx 73.Fn unlockpt 74does nothing. 75.Sh SEE ALSO 76.Xr ioctl 2 , 77.Xr grantpt 3 , 78.Xr posix_openpt 3 , 79.Xr ptsname 3 80.Sh STANDARDS 81The 82.Fn unlockpt 83function conforms to 84.St -p1003.1-2001 . 85Its first release was in 86.St -xpg4.2 . 87