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_EXIT(2)		   Linux Programmer's Manual		      _EXIT(2)

       _exit, _Exit - terminate the calling process

       #include <unistd.h>

       void _exit(int status);

       #include <stdlib.h>

       void _Exit(int status);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

	   _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L

       The function _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 process's par-
       ent is sent a SIGCHLD signal.

       The value status is returned to the parent  process  as	the  process's
       exit  status,  and  can be collected using one of the wait(2) family of

       The function _Exit() is equivalent to _exit().

       These functions do not return.

       POSIX.1-2001, POSIX.1-2008, SVr4, 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, and so on, see exit(3).

       The function _exit() is like exit(3), but does not call	any  functions
       registered with atexit(3) or on_exit(3).	 Open stdio(3) streams are not
       flushed.	 On the other hand, _exit() does close open file  descriptors,
       and this may cause an unknown delay, waiting for pending output to fin-
       ish.  If the delay is undesired, it may be  useful  to  call  functions
       like  tcflush(3)	 before	 calling  _exit().  Whether any pending I/O is
       canceled, and which pending I/O may be canceled upon _exit(), is imple-

   C library/kernel differences
       In  glibc  up  to version 2.3, the _exit() wrapper function invoked the
       kernel system call of the same name.   Since  glibc  2.3,  the  wrapper
       function	 invokes  exit_group(2),  in  order  to	 terminate  all of the
       threads in a process.

       execve(2), exit_group(2), fork(2), kill(2),  wait(2),  wait4(2),	 wait-
       pid(2), atexit(3), exit(3), on_exit(3), termios(3)

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       description of the project, information about reporting bugs,  and  the
       latest	  version     of     this    page,    can    be	   found    at

Linux				  2016-03-15			      _EXIT(2)