1.\" $NetBSD: getsid.2,v 1.10 2006/10/07 21:03:51 elad Exp $ 2.\" 3.\" Copyright (c) 1983, 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. Neither the name of the University nor the names of its contributors 15.\" may be used to endorse or promote products derived from this software 16.\" without specific prior written permission. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.\" @(#)getpgrp.2 8.1 (Berkeley) 6/4/93 31.\" 32.Dd October 7, 2006 33.Dt GETSID 2 34.Os 35.Sh NAME 36.Nm getsid 37.Nd get session ID 38.Sh LIBRARY 39.Lb libc 40.Sh SYNOPSIS 41.In unistd.h 42.Ft pid_t 43.Fn getsid "pid_t pid" 44.Sh DESCRIPTION 45The 46.Nm 47function returns the session ID of the process specified by 48.Ar pid . 49If 50.Ar pid 51is 0, the session ID of the calling process is returned. 52The session ID is defined as the process group ID of the 53process that is the session leader. 54.Sh ERRORS 55If an error occurs, 56.Nm 57returns \-1 and the global variable 58.Va errno 59is set to indicate the error, as follows: 60.Bl -tag -width Er 61.It Bq Er ESRCH 62No process can be found corresponding to that specified by 63.Ar pid . 64.El 65.Sh SEE ALSO 66.Xr getpgid 2 , 67.Xr setsid 2 , 68.Xr termios 4 69.Sh STANDARDS 70The 71.Fn getsid 72function conforms to 73.St -xpg4.2 . 74