1.\" Copyright (c) 1980 Regents of the University of California. 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.\" 3. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" from: @(#)_exit.2 6.6 (Berkeley) 7/25/91 33.\" $Id: _exit.2,v 1.4 1993/11/25 00:38:17 jtc Exp $ 34.\" 35.Dd July 25, 1991 36.Dt EXIT 2 37.Os BSD 4 38.Sh NAME 39.Nm _exit 40.Nd terminate the calling process 41.Sh SYNOPSIS 42.Fd #include <unistd.h> 43.Ft void 44.Fn _exit "int status" 45.Sh DESCRIPTION 46The 47.Fn _exit 48function 49terminates a process with the following consequences: 50.Bl -bullet 51.It 52All of the descriptors open in the calling process are closed. 53This may entail delays, for example, waiting for output to drain; 54a process in this state may not be killed, as it is already dying. 55.It 56If the parent process of the calling process has an outstanding 57.Xr wait 58call 59or is interested in the 60.Dv SIGCHLD 61signal, 62it is notified of the calling process's termination and 63the 64.Em status 65area is set as defined by 66.Xr wait 2 . 67.It 68The parent process-ID of all of the calling process's existing child 69processes are set to 1; the initialization process 70(see the DEFINITIONS section of 71.Xr intro 2 ) 72inherits each of these processes. 73Any stopped children are restarted with a hangup signal 74.Pq Dv SIGHUP . 75.El 76.Pp 77Most C programs call the library routine 78.Xr exit 3 , 79which flushes buffers, closes streams, unlinks temporary files, etc., 80before 81calling 82.Fn _exit . 83.Sh RETURN VALUE 84.Fn _exit 85can never return. 86.Sh SEE ALSO 87.Xr fork 2 , 88.Xr sigvec 2 , 89.Xr wait 2 , 90.Xr exit 3 91.Sh HISTORY 92An 93.Fn exit 94function call appeared in 95.At v6 . 96