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_EXIT(2)		  FreeBSD System Calls Manual		      _EXIT(2)

NAME
     _exit, _Exit -- terminate the calling process

SYNOPSIS
     #include <unistd.h>

     void
     _exit(int status);

     #include <stdlib.h>

     void
     _Exit(int status);

DESCRIPTION
     The _exit() and _Exit() functions terminate a process with	the following
     consequences:

     +o	 All threads in	the process are	terminated.

     +o	 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.

     +o	 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.)

     +o	 The parent process ID of all of the calling process's existing	child
	 processes are set to 1; the initialization process (see the DEFINI-
	 TIONS section of intro(2)) inherits each of these processes.

     +o	 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.

     +o	 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() and _Exit() can never return.

SEE ALSO
     fork(2), intro(2),	sigaction(2), wait(2), exit(3),	sysexits(3)

STANDARDS
     The _exit() function conform to IEEE Std 1003.1-2008 ("POSIX.1").	The
     _Exit() function conforms to ISO/IEC 9899:1999 ("ISO C99").

HISTORY
     An	exit() system call first appeared in Version 1 AT&T UNIX.  It accepts
     the status	argument since Version 2 AT&T UNIX.  An	_exit()	variant	first
     appeared in Version 7 AT&T	UNIX.  The _Exit() function appeared in
     OpenBSD 3.6.

FreeBSD	13.0		      September	10, 2015		  FreeBSD 13.0

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUES | SEE ALSO | STANDARDS | HISTORY

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