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/* $OpenBSD: select.c,v 1.3 2003/07/31 21:48:06 deraadt Exp $ */
/*
* Copyright (c) 1993, 1994, 1995, 1996 by Chris Provenzano and contributors,
* proven@mit.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 Chris Provenzano,
* the University of California, Berkeley, and contributors.
* 4. Neither the name of Chris Provenzano, the University, nor the names of
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY CHRIS PROVENZANO AND CONTRIBUTORS ``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 CHRIS PROVENZANO, THE REGENTS OR
* CONTRIBUTORS 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.
*/
/*
* Rudimentary test of select().
*/
#include <pthread.h>
#include <pthread_np.h>
#include <stdio.h>
#include <sys/fcntl.h>
#include <sys/types.h>
#include <sys/time.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#include "test.h"
#define NLOOPS 10000
int ntouts = 0;
static void *
bg_routine(void *arg)
{
char dot = '.';
int n;
SET_NAME("bg");
/* Busy loop, printing dots */
for (;;) {
pthread_yield();
write(STDOUT_FILENO, &dot, sizeof dot);
pthread_yield();
n = NLOOPS;
while (n-- > 0)
pthread_yield();
}
}
static void *
fg_routine(void *arg)
{
int flags;
int n;
fd_set r;
int fd = fileno((FILE *) arg);
int tty = isatty(fd);
int maxfd;
int nb;
char buf[128];
SET_NAME("fg");
/* Set the file descriptor to non-blocking */
flags = fcntl(fd, F_GETFL);
CHECKr(fcntl(fd, F_SETFL, flags | O_NONBLOCK));
for (;;) {
/* Print a prompt if it's a tty: */
if (tty) {
printf("type something> ");
fflush(stdout);
}
/* Select on the fdesc: */
FD_ZERO(&r);
FD_SET(fd, &r);
maxfd = fd;
errno = 0;
CHECKe(n = select(maxfd + 1, &r, (fd_set *) 0, (fd_set *) 0,
(struct timeval *) 0));
if (n > 0) {
/* Something was ready for read. */
printf("select returned %d\n", n);
while ((nb = read(fd, buf, sizeof(buf) - 1)) > 0) {
printf("read %d: `%.*s'\n", nb, nb, buf);
}
printf("last read was %d, errno = %d %s\n", nb, errno,
errno == 0 ? "success" : strerror(errno));
if (nb < 0)
ASSERTe(errno, == EWOULDBLOCK ||
errno == EAGAIN);
if (nb == 0)
break;
} else
ntouts++;
}
printf("read finished\n");
return (NULL);
}
int
main(int argc, char *argv[])
{
pthread_t bg_thread, fg_thread;
FILE * slpr;
/* Create a fdesc that will block for a while on read: */
CHECKn(slpr = popen("sleep 2; echo foo", "r"));
/* Create a busy loop thread that yields a lot: */
CHECKr(pthread_create(&bg_thread, NULL, bg_routine, 0));
/* Create the thread that reads the fdesc: */
CHECKr(pthread_create(&fg_thread, NULL, fg_routine, (void *) slpr));
/* Wait for the reader thread to finish */
CHECKr(pthread_join(fg_thread, NULL));
/* Clean up*/
CHECKe(pclose(slpr));
SUCCEED;
}
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