xref: /dragonfly/share/man/man9/at_exit.9 (revision 6e278935)
1.\"
2.\" Copyright (c) 1996 Julian Elischer
3.\"
4.\" All rights reserved.
5.\"
6.\" Redistribution and use in source and binary forms, with or without
7.\" modification, are permitted provided that the following conditions
8.\" are met:
9.\" 1. Redistributions of source code must retain the above copyright
10.\"    notice, this list of conditions and the following disclaimer.
11.\" 2. Redistributions in binary form must reproduce the above copyright
12.\"    notice, this list of conditions and the following disclaimer in the
13.\"    documentation and/or other materials provided with the distribution.
14.\"
15.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR
16.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT,
19.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25.\"
26.\" $FreeBSD: src/share/man/man9/at_exit.9,v 1.10.2.7 2001/12/17 11:30:18 ru Exp $
27.\"
28.Dd August 15, 1996
29.Dt AT_EXIT 9
30.Os
31.Sh NAME
32.Nm at_exit ,
33.Nm rm_at_exit
34.Nd ask that a function be run at exit
35.Sh SYNOPSIS
36.In sys/types.h
37.In sys/systm.h
38.Ft typedef\ void ( exitlist_fn ) ( struct\ proc\ * ) ;
39.Pp
40.Ft int
41.Fn at_exit "exitlist_fn func"
42.Ft int
43.Fn rm_at_exit "exitlist_fn func"
44.Sh DESCRIPTION
45The
46.Nm
47facility allows a kernel module to ensure that it is notified
48at any process exit.
49The function
50.Fa func
51is called with the a pointer to the exiting process's proc structure.
52.Pp
53If the requirement for notification is removed, then the function
54.Fn rm_at_exit
55must be called with the exact
56.Fa func
57argument as the corresponding call to
58.Fn at_exit .
59.Sh RETURN VALUES
60The
61.Fn at_exit
62function returns an
63.Va errno ,
640 meaning success.
65The
66.Fn rm_at_exit
67function returns the number of items removed (should be 0 or 1).
68.Sh SEE ALSO
69.Xr _exit 2
70.Sh HISTORY
71The
72.Fn at_exit
73function appeared in
74.Fx 2.2 .
75.Sh AUTHORS
76The function was written by
77.An Julian Elischer Aq julian@FreeBSD.org .
78