1.\" Copyright (c) 1980 Regents of the University of California. 2.\" All rights reserved. 3.\" 4.\" %sccs.include.redist.man% 5.\" 6.\" @(#)_exit.2 6.6 (Berkeley) 07/25/91 7.\" 8.Dd 9.Dt EXIT 2 10.Os BSD 4 11.Sh NAME 12.Nm _exit 13.Nd terminate the calling process 14.Sh SYNOPSIS 15.Fd #include <unistd.h> 16.Ft void volatile 17.Fn _exit "int status" 18.Sh DESCRIPTION 19The 20.Fn _exit 21function 22terminates a process with the following consequences: 23.Bl -bullet 24.It 25All of the descriptors open in the calling process are closed. 26This may entail delays, for example, waiting for output to drain; 27a process in this state may not be killed, as it is already dying. 28.It 29If the parent process of the calling process has an outstanding 30.Xr wait 31call 32or is interested in the 33.Dv SIGCHLD 34signal, 35it is notified of the calling process's termination and 36the 37.Em status 38area is set as defined by 39.Xr wait 2 . 40.It 41The parent process-ID of all of the calling process's existing child 42processes are set to 1; the initialization process 43(see the DEFINITIONS section of 44.Xr intro 2 ) 45inherits each of these processes. 46Any stopped children are restarted with a hangup signal 47.Pq Dv SIGHUP . 48.El 49.Pp 50Most C programs call the library routine 51.Xr exit 3 , 52which flushes buffers, closes streams, unlinks temporary files, etc., 53before 54calling 55.Fn _exit . 56.Sh RETURN VALUE 57.Fn _exit 58can never return. 59.Sh SEE ALSO 60.Xr fork 2 , 61.Xr sigvec 2 , 62.Xr wait 2 , 63.Xr exit 3 64.Sh HISTORY 65An 66.Nm exit 67function call appeared in 68.At v6 . 69