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/* $OpenBSD: test_select.c,v 1.4 1999/11/28 12:31:42 d Exp $ */
/*
* 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 "test.h"
#define NLOOPS 10000
int ntouts = 0;
void *
bg_routine(arg)
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();
}
}
void *
fg_routine(arg)
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(argc, argv)
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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