_EXIT(2) BSD Programmer's Manual _EXIT(2)NAME
_exit - terminate the calling process
SYNOPSIS
#include <unistd.h>
void
_exit(int status);
DESCRIPTION
The _exit() function terminates a process with the following conse-
quences:
+ All open file descriptors 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 status is set as defined by
wait(2). (Note that typically only the lower 8 bits of status are
passed on to the parent, thus negative values have less meaning.)
+ 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 and SIGCONT sig-
nals 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 re-
voked.
Most C programs call the library routine exit(3), which flushes buffers,
closes streams, unlinks temporary files, etc., and then calls _exit().
RETURN VALUES_exit() can never return.
SEE ALSOfork(2), intro(2), sigaction(2), wait(2), _Exit(3), exit(3), sysexits(3)STANDARDS
The _exit() function is defined by IEEE Std 1003.1-1988 ("POSIX").
MirOS BSD #10-current June 4, 1993 1