NAME
_Exit, _exit —
terminate the calling
process
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <stdlib.h>
void
_Exit(
int
status);
#include <unistd.h>
void
_exit(
int
status);
DESCRIPTION
The
_Exit() and
_exit() functions are
equivalent. They each terminate a process with the following consequences:
- All of the descriptors open in the calling process are
closed. This may entail delays, for example, waiting for output to drain;
a process in this state may not be killed, as it is already dying.
- If the parent process of the calling process has an
outstanding wait(2) call or
catches the
SIGCHLD
signal, it is notified of the
calling process's termination and the status is set as
defined by wait(2).
- The parent process-ID of all of the calling process's
existing child processes are set to 1; the initialization process (see the
DEFINITIONS section of
intro(2)) inherits each of
these processes.
- If the termination of the process causes any process
group to become orphaned (usually because the parents of all members of
the group have now exited; see “orphaned process group” in
intro(2)), and if any member
of the orphaned group is stopped, the
SIGHUP
signal and the SIGCONT
signal are sent to all
members of the newly-orphaned process group.
- If the process is a controlling process (see
intro(2)), the
SIGHUP
signal is sent to the foreground process
group of the controlling terminal, and all current access to the
controlling terminal is revoked.
Most C programs call the library routine
exit(3), which flushes buffers,
closes streams, unlinks temporary files, etc., before calling
_exit().
RETURN VALUES
_Exit() and
_exit() can never return.
SEE ALSO
fork(2),
sigaction(2),
wait(2),
exit(3)
STANDARDS
The
_exit() function conforms to
IEEE Std
1003.1-1990 (“POSIX.1”). The
_Exit()
function conforms to
ISO/IEC 9899:1999
(“ISO C99”).