home   contributing   bugs   download   online pages  

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | CONFORMING TO | NOTES | SEE ALSO | COLOPHON


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

NAME         top

       _exit, _Exit - terminate the calling process

SYNOPSIS         top

       #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)):

       _Exit(): _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE; or cc -std=c99

DESCRIPTION         top

       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 parent 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 calls.

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

RETURN VALUE         top

       These functions do not return.

CONFORMING TO         top

       SVr4, POSIX.1-2001, 4.3BSD.  The function _Exit() was introduced by C99.

NOTES         top

       For a discussion on the effects of an exit, the transmission of exit status,
       zombie processes, signals sent, etc., see exit(3).

       The function _exit() is like exit(3), but does not call any functions
       registered with atexit(3) or on_exit(3).  Whether it flushes standard I/O
       buffers and removes temporary files created with tmpfile(3) 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(3) before
       calling _exit().  Whether any pending I/O is canceled, and which pending I/O
       may be canceled upon _exit(), is implementation-dependent.

       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.

SEE ALSO         top

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

COLOPHON         top

       This page is part of release 3.23 of the Linux man-pages project.  A
       description of the project, and information about reporting bugs, can be found
       at http://www.kernel.org/doc/man-pages/.

Linux                                 2008-11-27                             _EXIT(2)