1.\" Copyright (c) 1990, 1991 The Regents of the University of California. 2.\" All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" the American National Standards Committee X3, on Information 6.\" Processing Systems. 7.\" 8.\" Redistribution and use in source and binary forms, with or without 9.\" modification, are permitted provided that the following conditions 10.\" are met: 11.\" 1. Redistributions of source code must retain the above copyright 12.\" notice, this list of conditions and the following disclaimer. 13.\" 2. Redistributions in binary form must reproduce the above copyright 14.\" notice, this list of conditions and the following disclaimer in the 15.\" documentation and/or other materials provided with the distribution. 16.\" 3. 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.\" $OpenBSD: exit.3,v 1.17 2024/08/12 20:53:09 guenther Exp $ 33.\" 34.Dd $Mdocdate: August 12 2024 $ 35.Dt EXIT 3 36.Os 37.Sh NAME 38.Nm exit 39.Nd perform normal program termination 40.Sh SYNOPSIS 41.In stdlib.h 42.Ft void 43.Fn exit "int status" 44.Sh DESCRIPTION 45The 46.Fn exit 47function terminates a process. 48.Pp 49Before termination it performs the following functions in the 50order listed: 51.Bl -enum -offset indent 52.It 53Call the functions registered with the 54.Xr atexit 3 55function, in the reverse order of their registration. 56.It 57Flush and close all open streams. 58.It 59Unlink all files created with the 60.Xr tmpfile 3 61function. 62.El 63.Pp 64Following this, 65.Fn exit 66calls 67.Xr _exit 2 . 68Note that typically 69.Xr _exit 2 70only passes the lower 8 bits of 71.Fa status 72on to the parent, thus negative values have less meaning. 73.Sh RETURN VALUES 74The 75.Fn exit 76function never returns. 77.Sh SEE ALSO 78.Xr _exit 2 , 79.Xr atexit 3 , 80.Xr fflush 3 , 81.Xr intro 3 , 82.Xr sysexits 3 , 83.Xr tmpfile 3 84.Sh STANDARDS 85The 86.Fn exit 87function conforms to 88.St -p1003.1-2024 . 89.Sh HISTORY 90An 91.Fn exit 92function first appeared as a system call in 93.At v1 . 94It has accepted the 95.Fa status 96argument since 97.At v2 . 98In 99.At v7 , 100the bare system call was renamed to 101.Xr _exit 2 . 102