Add at_quick_exit(3) and quick_exit(3) manual pages.
[dragonfly.git] / lib / libc / stdlib / atexit.3
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32.\" @(#)atexit.3 8.1 (Berkeley) 6/4/93
5d0641a4 33.\" $FreeBSD: src/lib/libc/stdlib/atexit.3,v 1.11 2007/01/09 00:28:09 imp Exp $
984263bc 34.\"
5d0641a4 35.Dd September 6, 2002
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36.Dt ATEXIT 3
37.Os
38.Sh NAME
39.Nm atexit
40.Nd register a function to be called on exit
41.Sh LIBRARY
42.Lb libc
43.Sh SYNOPSIS
44.In stdlib.h
45.Ft int
46.Fn atexit "void (*function)(void)"
47.Sh DESCRIPTION
48The
49.Fn atexit
50function
51registers the given
5d0641a4 52.Fa function
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53to be called at program exit, whether via
54.Xr exit 3
55or via return from the program's
5d0641a4 56.Fn main .
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57Functions so registered are called in reverse order;
58no arguments are passed.
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59.Pp
60These functions must not call
61.Fn exit ;
62if it should be necessary to terminate the process while in such a
63function, the
64.Xr _exit 2
65function should be used.
66(Alternatively, the function may cause abnormal
67process termination, for example by calling
68.Xr abort 3 . )
69.Pp
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70At least 32 functions can always be registered,
71and more are allowed as long as sufficient memory can be allocated.
5d0641a4 72.\" XXX {ATEXIT_MAX} is not implemented yet
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73.Sh RETURN VALUES
74.Rv -std atexit
75.Sh ERRORS
76.Bl -tag -width Er
77.It Bq Er ENOMEM
78No memory was available to add the function to the list.
79The existing list of functions is unmodified.
80.El
81.Sh SEE ALSO
f3adbb3c 82.Xr at_quick_exit 3 ,
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83.Xr exit 3
84.Sh STANDARDS
85The
86.Fn atexit
87function
88conforms to
89.St -isoC .