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/* $OpenBSD: kqueue-pipe.c,v 1.2 2002/01/07 00:11:07 provos Exp $ */
/*
* Copyright 2001 Niels Provos <provos@citi.umich.edu>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Niels Provos.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/types.h>
#include <sys/time.h>
#include <sys/event.h>
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
int
main(int argc, char **argv)
{
int kq;
int n;
int fd[2];
struct kevent ev;
struct timespec ts;
char buf[8000];
if (pipe(fd) == -1)
exit(1);
if (fcntl(fd[1], F_SETFL, O_NONBLOCK) == -1)
exit(1);
if ((kq = kqueue()) == -1)
exit(1);
ev.ident = fd[1];
ev.filter = EVFILT_WRITE;
ev.flags = EV_ADD | EV_ENABLE;
n = kevent(kq, &ev, 1, NULL, 0, NULL);
if (n == -1)
exit(1);
while ((n = write(fd[1], buf, sizeof(buf))) == sizeof(buf))
;
ts.tv_sec = 0;
ts.tv_nsec = 0;
n = kevent(kq, NULL, 0, &ev, 1, &ts);
if (n != 0)
exit(1);
read(fd[0], buf, sizeof(buf));
ts.tv_sec = 0;
ts.tv_nsec = 0;
n = kevent(kq, NULL, 0, &ev, 1, &ts);
if (n == -1 || n == 0)
exit(1);
exit(0);
}
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