xref: /dragonfly/lib/libc/stdlib/exit.3 (revision 6b5c5d0d)
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36.\"     @(#)exit.3	8.1 (Berkeley) 6/4/93
37.\" $FreeBSD: src/lib/libc/stdlib/exit.3,v 1.6.2.4 2001/12/14 18:33:58 ru Exp $
38.\" $DragonFly: src/lib/libc/stdlib/exit.3,v 1.3 2007/06/15 19:36:33 swildner Exp $
39.\"
40.Dd June 15, 2007
41.Dt EXIT 3
42.Os
43.Sh NAME
44.Nm exit ,
45.Nm _Exit
46.Nd perform normal program termination
47.Sh LIBRARY
48.Lb libc
49.Sh SYNOPSIS
50.In stdlib.h
51.Ft void
52.Fn exit "int status"
53.Ft void
54.Fn _Exit "int status"
55.Sh DESCRIPTION
56The
57.Fn exit
58and
59.Fn _Exit
60functions terminate a process.
61.Pp
62Before termination,
63.Fn exit
64performs the following functions in the order listed:
65.Bl -enum -offset indent
66.It
67Call the functions registered with the
68.Xr atexit 3
69function, in the reverse order of their registration.
70.It
71Flush all open output streams.
72.It
73Close all open streams.
74.It
75Unlink all files created with the
76.Xr tmpfile 3
77function.
78.El
79.Pp
80The C99 function
81.Fn _Exit
82terminates without calling the functions registered with
83.Xr atexit 3
84by just calling
85.Xr _exit 2 .
86Code intended to be portable should always use
87.Xr _exit 2
88directly as it is defined by
89.St -susv2
90as well.
91.Pp
92Passing arbitrary values back to the environment as
93.Ar status
94is considered bad style;
95you should use the values
96.Dv EXIT_SUCCESS
97and
98.Dv EXIT_FAILURE .
99If portability is not a concern, you may
100use the values described in
101.Xr sysexits 3 .
102.Sh RETURN VALUES
103The
104.Fn exit
105and
106.Fn _Exit
107functions never return.
108.Sh SEE ALSO
109.Xr _exit 2 ,
110.Xr atexit 3 ,
111.Xr intro 3 ,
112.Xr sysexits 3 ,
113.Xr tmpfile 3
114.Sh STANDARDS
115The
116.Fn exit
117and
118.Fn _Exit
119functions conform to
120.St -isoC-99 .
121