1 .\" Copyright (C) 2001 Andries Brouwer <aeb@cwi.nl>.
3 .\" %%%LICENSE_START(VERBATIM)
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13 .\" Since the Linux kernel and libraries are constantly changing, this
14 .\" manual page may be incorrect or out-of-date. The author(s) assume no
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25 .\" FIXME There are a lot of other process termination actions that
26 .\" could be listed on this page. See, for example, the list in the
27 .\" POSIX exit(3p) page.
29 .TH EXIT 3 2014-03-25 "Linux" "Linux Programmer's Manual"
31 exit \- cause normal process termination
34 .B #include <stdlib.h>
36 .BI "void exit(int " status );
41 function causes normal process termination and the
42 value of \fIstatus & 0377\fP is returned to the parent
46 All functions registered with
50 are called, in the reverse order of their registration.
51 (It is possible for one of these functions to use
55 to register an additional
56 function to be executed during exit processing;
57 the new registration is added to the front of the list of functions
58 that remain to be called.)
59 If one of these functions does not return
62 or kills itself with a signal),
63 then none of the remaining functions is called,
64 and further exit processing (in particular, flushing of
66 streams) is abandoned.
67 If a function has been registered multiple times using
71 then it is called as many times as it was registered.
75 streams are flushed and closed.
80 The C standard specifies two constants,
81 \fBEXIT_SUCCESS\fP and \fBEXIT_FAILURE\fP,
84 to indicate successful or unsuccessful
85 termination, respectively.
89 function does not return.
91 .SS Multithreading (see pthreads(7))
94 function uses a global variable that is not protected,
95 so it is not thread-safe.
97 SVr4, 4.3BSD, POSIX.1-2001, C89, C99.
100 It is undefined what happens if one of the
101 functions registered using
111 removes registrations created using
120 is slightly more portable
121 (to non-UNIX environments) than the use of 0 and some nonzero value
123 In particular, VMS uses a different convention.
125 BSD has attempted to standardize exit codes; see the file
130 the exit status must be transmitted to the
132 There are three cases.
133 If the parent has set
139 the status is discarded.
140 If the parent was waiting on the child,
141 it is notified of the exit status.
142 In both cases the exiting
143 process dies immediately.
144 If the parent has not indicated that
145 it is not interested in the exit status, but is not waiting,
146 the exiting process turns into a "zombie" process
147 (which is nothing but a container for the single byte representing
148 the exit status) so that the parent can learn the exit status when
149 it later calls one of the
153 If the implementation supports the
156 is sent to the parent.
157 If the parent has set
159 it is undefined whether a
163 If the process is a session leader and its controlling terminal
164 is the controlling terminal of the session, then each process in
165 the foreground process group of this controlling terminal
168 signal, and the terminal is disassociated
169 from this session, allowing it to be acquired by a new controlling
172 If the exit of the process causes a process group to become orphaned,
173 and if any member of the newly orphaned process group is stopped,
179 sent to each process in this process group.
182 for an explanation of orphaned process groups.
191 This page is part of release 3.68 of the Linux
194 A description of the project,
195 information about reporting bugs,
196 and the latest version of this page,
198 \%http://www.kernel.org/doc/man\-pages/.