1.\" Copyright (c) 2009 Ed Schouten <ed@FreeBSD.org> 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23.\" SUCH DAMAGE. 24.\" 25.Dd November 28, 2022 26.Dt TCSETSID 3 27.Os 28.Sh NAME 29.Nm tcsetsid 30.Nd set session ID associated with a controlling terminal 31.Sh LIBRARY 32.Lb libc 33.Sh SYNOPSIS 34.In termios.h 35.Ft int 36.Fn tcsetsid "int fd" "pid_t pid" 37.Sh DESCRIPTION 38The 39.Fn tcsetsid 40function sets associates a session identified by 41.Fa pid 42with a controlling terminal specified by 43.Fa fd . 44.Pp 45This implementation only allows the controlling terminal to be changed 46by the session leader itself. 47This implies that 48.Fa pid 49always has to be equal to the process ID. 50.Pp 51It is unsupported to associate with a terminal that already has an 52associated session. 53Conversely, it is also unsupported to associate to a terminal when 54the session is already associated with a different terminal. 55.Sh ERRORS 56If an error occurs, 57.Fn tcsetsid 58returns -1 and the global variable 59.Va errno 60is set to indicate the error, as follows: 61.Bl -tag -width Er 62.It Bq Er EBADF 63The 64.Fa fd 65argument is not a valid file descriptor. 66.It Bq Er ENOTTY 67The file descriptor represented by 68.Fa fd 69is not a terminal. 70.It Bq Er EINVAL 71The 72.Fa pid 73argument is not equal to the session ID of the calling process. 74.It Bq Er EPERM 75The calling process is not a session leader. 76.It Bq Er EPERM 77The session already has an associated terminal or the terminal already 78has an associated session. 79.El 80.Sh SEE ALSO 81.Xr getsid 2 , 82.Xr setsid 2 , 83.Xr tcgetpgrp 3 , 84.Xr tcgetsid 3 85.Sh HISTORY 86A 87.Fn tcsetsid 88function first appeared in QNX. 89It does not comply to any standard. 90