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_exit() - Unix, Linux System Call
_exit, _Exit - terminate the current process
void _exit(int status);
void _Exit(int status);
_exit() terminates the calling process "immediately". Any open file descriptors
belonging to the process are closed; any children of the process are
inherited by process 1,
init, and the processs parent is sent a
status is returned to the parent process as the processs exit status, and
can be collected using one of the
wait() family of calls.
_Exit() is equivalent to
These functions do not return.
SVr4, POSIX.1-2001, 4.3BSD.
The function _Exit() was introduced by C99.
For a discussion on the effects of an exit, the transmission of
exit status, zombie processes, signals sent, etc., see
_exit() is like exit(), but does not call any
functions registered with
on_exit(). Whether it flushes
standard I/O buffers and removes temporary files created with
is implementation dependent.
On the other hand,
_exit() does close open file descriptors, and this may cause an unknown delay,
waiting for pending output to finish. If the delay is undesired,
it may be useful to call functions like tcflush() before
Whether any pending I/O is cancelled, and which pending I/O may be
cancelled upon _exit(), is implementation-dependent.