1.\" Copyright (c) 1980, 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. 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.\" @(#)_exit.2 8.1 (Berkeley) 6/4/93 33.\" $FreeBSD$ 34.\" 35.Dd June 4, 1993 36.Dt EXIT 2 37.Os 38.Sh NAME 39.Nm _exit 40.Nd terminate the calling process 41.Sh LIBRARY 42.Lb libc 43.Sh SYNOPSIS 44.Fd #include <unistd.h> 45.Ft void 46.Fn _exit "int status" 47.Sh DESCRIPTION 48The 49.Fn _exit 50function 51terminates a process with the following consequences: 52.Bl -bullet 53.It 54All of the descriptors open in the calling process are closed. 55This may entail delays, for example, waiting for output to drain; 56a process in this state may not be killed, as it is already dying. 57.It 58If the parent process of the calling process has an outstanding 59.Xr wait 2 60call 61or catches the 62.Dv SIGCHLD 63signal, 64it is notified of the calling process's termination and 65the 66.Em status 67is set as defined by 68.Xr wait 2 . 69.It 70The parent process-ID of all of the calling process's existing child 71processes are set to 1; the initialization process 72(see the 73.Sx DEFINITIONS 74section of 75.Xr intro 2 ) 76inherits each of these processes. 77.It 78If the termination of the process causes any process group 79to become orphaned (usually because the parents of all members 80of the group have now exited; see 81.Dq orphaned process group 82in 83.Xr intro 2 ) , 84and if any member of the orphaned group is stopped, 85the 86.Dv SIGHUP 87signal and the 88.Dv SIGCONT 89signal are sent to all members of the newly-orphaned process group. 90.It 91If the process is a controlling process (see 92.Xr intro 2 ) , 93the 94.Dv SIGHUP 95signal is sent to the foreground process group of the controlling terminal, 96and all current access to the controlling terminal is revoked. 97.El 98.Pp 99Most C programs call the library routine 100.Xr exit 3 , 101which flushes buffers, closes streams, unlinks temporary files, etc., 102before 103calling 104.Fn _exit . 105.Sh RETURN VALUES 106.Fn _exit 107can never return. 108.Sh SEE ALSO 109.Xr fork 2 , 110.Xr sigaction 2 , 111.Xr wait 2 , 112.Xr exit 3 113.Sh STANDARDS 114The 115.Fn _exit 116function call is expected to conform to 117.St -p1003.1-90 . 118.Sh HISTORY 119An 120.Fn _exit 121function call appeared in 122.At v7 . 123