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#include <pthread.h>
#include <stdio.h>
#ifndef ultrix
#include <sys/fcntl.h>
#else /* ultrix */
#include <fcntl.h>
#endif /* !ultrix */
#include <sys/types.h>
#include <sys/time.h>
#ifdef hpux
#include <sys/file.h>
#endif /* hpux */
#include <errno.h>
#define NLOOPS 1000
int ntouts = 0;
void *
bg_routine(void *arg)
{
write(1,"bg routine running\n",19);
/*pthread_dump_state();*/
while (1) {
int n;
char dot;
dot = '.';
pthread_yield();
write(1,&dot,1);
pthread_yield();
n = NLOOPS;
while (n-- > 0)
pthread_yield();
}
}
void *
fg_routine(void *arg)
{
int flags, stat, nonblock_flag;
static struct timeval tout = { 0, 500000 };
#if 0
#if defined(hpux) || defined(__alpha)
nonblock_flag = O_NONBLOCK;
#else
nonblock_flag = FNDELAY;
#endif
printf("fg_routine running\n");
flags = fcntl(0, F_GETFL, 0);
printf("stdin flags b4 anything = %x\n", flags);
stat = fcntl(0, F_SETFL, flags | nonblock_flag);
if (stat < 0) {
printf("fcntl(%x) => %d\n", nonblock_flag, errno);
printf("could not set nonblocking i/o on stdin [oldf %x, stat %d]\n",
flags, stat);
exit(1);
}
printf("stdin flags = 0x%x after turning on %x\n", flags, nonblock_flag);
#endif
while (1) {
int n;
fd_set r;
FD_ZERO(&r);
FD_SET(0,&r);
printf("select>");
n = select(1, &r, (fd_set*)0, (fd_set*)0, (struct timeval *)0);
if (n < 0) {
perror ("select");
exit(1);
} else if (n > 0) {
int nb;
char buf[128];
printf("=> select returned: %d\n", n);
while ((nb = read(0, buf, sizeof(buf)-1)) >= 0) {
buf[nb] = '\0';
printf("read %d: |%s|\n", nb, buf);
}
printf("=> out of read loop: %d / %d\n", nb, errno);
if (nb < 0) {
if (errno != EWOULDBLOCK && errno != EAGAIN) {
perror ("read");
exit(1);
}
}
} else
ntouts++;
}
}
main(int argc, char **argv)
{
pthread_t bg_thread, fg_thread;
int junk;
pthread_init();
setbuf(stdout,NULL);
setbuf(stderr,NULL);
if (argc > 1) {
if (pthread_create(&bg_thread, NULL, bg_routine, 0) < 0) {
printf("error: could not create bg thread\n");
exit(1);
}
}
if (pthread_create(&fg_thread, NULL, fg_routine, 0) < 0) {
printf("error: could not create fg thread\n");
exit(1);
}
printf("threads forked: bg=%lx fg=%lx\n", bg_thread, fg_thread);
/*pthread_dump_state();*/
printf("initial thread %lx joining fg...\n", pthread_self());
pthread_join(fg_thread, (void **)&junk);
}
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