.\"	$NetBSD: atexit.3,v 1.11 2013/04/26 19:37:04 wiz Exp $
.\"
.\" Copyright (c) 1990, 1991, 1993
.\"	The Regents of the University of California.  All rights reserved.
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.\" This code is derived from software contributed to Berkeley by
.\" Chris Torek and the American National Standards Committee X3,
.\" on Information Processing Systems.
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.\"     from: @(#)atexit.3	8.1 (Berkeley) 6/4/93
.\"
.Dd June 4, 1993
.Dt ATEXIT 3
.Os
.Sh NAME
.Nm atexit
.Nd register a function to be called on exit
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In stdlib.h
.Ft int
.Fn atexit "void (*function)(void)"
.Sh DESCRIPTION
The
.Fn atexit
function
registers the given
.Ar function
to be called at program exit, whether via
.Xr exit 3
or via return from the program's
.Em main .
Functions so registered are called in reverse order;
no arguments are passed.
At least 32 functions can always be registered,
and more are allowed as long as sufficient memory can be allocated.
.Sh RETURN VALUES
.Rv -std atexit
.Sh ERRORS
.Bl -tag -width Er
.It Bq Er ENOMEM
No memory was available to add the function to the list.
The existing list of functions is unmodified.
.El
.Sh SEE ALSO
.Xr at_quick_exit 3 ,
.Xr exit 3 ,
.Xr quick_exit 3
.Sh STANDARDS
The
.Fn atexit
function
conforms to
.St -ansiC .