1.\" Copyright (c) 2008 Ed Schouten <ed@FreeBSD.org> 2.\" All rights reserved. 3.\" 4.\" Portions of this software were developed under sponsorship from Snow 5.\" B.V., the Netherlands. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" Portions of this text are reprinted and reproduced in electronic form 29.\" from IEEE Std 1003.1, 2004 Edition, Standard for Information Technology -- 30.\" Portable Operating System Interface (POSIX), The Open Group Base 31.\" Specifications Issue 6, Copyright (C) 2001-2004 by the Institute of 32.\" Electrical and Electronics Engineers, Inc and The Open Group. In the 33.\" event of any discrepancy between this version and the original IEEE and 34.\" The Open Group Standard, the original IEEE and The Open Group Standard is 35.\" the referee document. The original Standard can be obtained online at 36.\" http://www.opengroup.org/unix/online.html. 37.\" 38.\" $FreeBSD$ 39.\" 40.Dd March 21, 2013 41.Dt POSIX_OPENPT 2 42.Os 43.Sh NAME 44.Nm posix_openpt 45.Nd "open a pseudo-terminal device" 46.Sh LIBRARY 47.Lb libc 48.Sh SYNOPSIS 49.In stdlib.h 50.In fcntl.h 51.Ft int 52.Fn posix_openpt "int oflag" 53.Sh DESCRIPTION 54The 55.Fn posix_openpt 56function allocates a new pseudo-terminal and establishes a connection 57with its master device. 58A slave device shall be created in 59.Pa /dev/pts . 60After the pseudo-terminal has been allocated, the slave device should 61have the proper permissions before it can be used (see 62.Xr grantpt 3 ) . 63The name of the slave device can be determined by calling 64.Xr ptsname 3 . 65.Pp 66The file status flags and file access modes of the open file description 67shall be set according to the value of 68.Fa oflag . 69Values for 70.Fa oflag 71are constructed by a bitwise-inclusive OR of flags from the following 72list, defined in 73.In fcntl.h : 74.Bl -tag -width ".Dv O_CLOEXEC" 75.It Dv O_RDWR 76Open for reading and writing. 77.It Dv O_NOCTTY 78If set 79.Fn posix_openpt 80shall not cause the terminal device to become the controlling terminal 81for the process. 82.It Dv O_CLOEXEC 83Set the close-on-exec flag for the new file descriptor. 84.El 85.Pp 86The 87.Fn posix_openpt 88function shall fail when 89.Fa oflag 90contains other values. 91.Sh RETURN VALUES 92Upon successful completion, the 93.Fn posix_openpt 94function shall allocate a new pseudo-terminal device and return a 95non-negative integer representing a file descriptor, which is connected 96to its master device. 97Otherwise, -1 shall be returned and errno set to indicate the error. 98.Sh ERRORS 99The 100.Fn posix_openpt 101function shall fail if: 102.Bl -tag -width Er 103.It Bq Er ENFILE 104The system file table is full. 105.It Bq Er EINVAL 106The value of 107.Fa oflag 108is not valid. 109.It Bq Er EAGAIN 110Out of pseudo-terminal resources. 111.El 112.Sh SEE ALSO 113.Xr pts 4 , 114.Xr ptsname 3 , 115.Xr tty 4 116.Sh STANDARDS 117The 118.Fn posix_openpt 119function conforms to 120.St -p1003.1-2001 . 121The ability to use 122.Dv O_CLOEXEC 123is an extension to the standard. 124.Sh HISTORY 125The 126.Fn posix_openpt 127function appeared in 128.Fx 5.0 . 129In 130.Fx 8.0 , 131this function was changed to a system call. 132.Sh NOTES 133The flag 134.Dv O_NOCTTY 135is included for compatibility; in 136.Fx , 137opening a terminal does not cause it to become a process's controlling 138terminal. 139.Sh AUTHORS 140.An Ed Schouten Aq ed@FreeBSD.org 141