exit(3)

NAME

exit, _Exit - perform normal program termination

Standard C Library (libc, -lc)

#include <stdlib.h>
void
exit(int status);
void
_Exit(int status);

The exit() and _Exit() functions terminate a process.

Before termination, exit() performs the following functions
in the order listed:: 1. Call the functions registered with the atexit(3)
function, in the reverse order of their registration.
2. Flush all open output streams.
3. Close all open streams.
4. Unlink all files created with the tmpfile(3)
function.
The _Exit() function terminates without calling the func
tions registered with the atexit(3) function, and may or may not perform the
other actions listed. Both functions make the low-order eight bits of the
status argument available to a parent process which has called a
wait(2)-family function.
The C Standard (ISO/IEC 9899:1999 (``ISO C99'')) defines the
values 0, EXIT_SUCCESS, and EXIT_FAILURE as possible values of status.
Cooperating processes may use other values; in a program which might be
called by a mail transfer agent, the values described in sysexits(3) may
be used to provide more information to the parent process.
Note that exit() does nothing to prevent bottomless recur
sion should a
function registered using atexit(3) itself call exit().
Such functions
must call _Exit() instead (although this has other effects
as well which may not be desired).

The exit() and _Exit() functions never return.