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.\" $FreeBSD$ 26.\" 27.Dd November 28, 2022 28.Dt TCSETSID 3 29.Os 30.Sh NAME 31.Nm tcsetsid 32.Nd set session ID associated with a controlling terminal 33.Sh LIBRARY 34.Lb libc 35.Sh SYNOPSIS 36.In termios.h 37.Ft int 38.Fn tcsetsid "int fd" "pid_t pid" 39.Sh DESCRIPTION 40The 41.Fn tcsetsid 42function sets associates a session identified by 43.Fa pid 44with a controlling terminal specified by 45.Fa fd . 46.Pp 47This implementation only allows the controlling terminal to be changed 48by the session leader itself. 49This implies that 50.Fa pid 51always has to be equal to the process ID. 52.Pp 53It is unsupported to associate with a terminal that already has an 54associated session. 55Conversely, it is also unsupported to associate to a terminal when 56the session is already associated with a different terminal. 57.Sh ERRORS 58If an error occurs, 59.Fn tcsetsid 60returns -1 and the global variable 61.Va errno 62is set to indicate the error, as follows: 63.Bl -tag -width Er 64.It Bq Er EBADF 65The 66.Fa fd 67argument is not a valid file descriptor. 68.It Bq Er ENOTTY 69The file descriptor represented by 70.Fa fd 71is not a terminal. 72.It Bq Er EINVAL 73The 74.Fa pid 75argument is not equal to the session ID of the calling process. 76.It Bq Er EPERM 77The calling process is not a session leader. 78.It Bq Er EPERM 79The session already has an associated terminal or the terminal already 80has an associated session. 81.El 82.Sh SEE ALSO 83.Xr getsid 2 , 84.Xr setsid 2 , 85.Xr tcgetpgrp 3 , 86.Xr tcgetsid 3 87.Sh HISTORY 88A 89.Fn tcsetsid 90function first appeared in QNX. 91It does not comply to any standard. 92