1.\" Copyright (c) 1991, 1993 2.\" The Regents of the University of California. 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.\" 3. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.\" @(#)tcgetpgrp.3 8.1 (Berkeley) 6/4/93 29.\" $FreeBSD$ 30.\" 31.Dd November 28, 2022 32.Dt TCGETPGRP 3 33.Os 34.Sh NAME 35.Nm tcgetpgrp 36.Nd get foreground process group ID 37.Sh LIBRARY 38.Lb libc 39.Sh SYNOPSIS 40.In unistd.h 41.Ft pid_t 42.Fn tcgetpgrp "int fd" 43.Sh DESCRIPTION 44The 45.Fn tcgetpgrp 46function returns the value of the process group ID of the foreground 47process group associated with the terminal device. 48If there is no foreground process group, 49.Fn tcgetpgrp 50returns an invalid process ID. 51.Sh ERRORS 52If an error occurs, 53.Fn tcgetpgrp 54returns -1 and the global variable 55.Va errno 56is set to indicate the error, as follows: 57.Bl -tag -width Er 58.It Bq Er EBADF 59The 60.Fa fd 61argument is not a valid file descriptor. 62.It Bq Er ENOTTY 63The calling process does not have a controlling terminal or the 64underlying terminal device represented by 65.Fa fd 66is not the controlling terminal. 67.El 68.Sh SEE ALSO 69.Xr setpgid 2 , 70.Xr setsid 2 , 71.Xr tcsetpgrp 3 72.Sh STANDARDS 73The 74.Fn tcgetpgrp 75function is expected to be compliant with the 76.St -p1003.1-88 77specification. 78