int
main(int argc, char **argv)
{
int i, nloop, signo;
pid_t childpid, parentpid;
sigset_t newmask;
if (argc != 2)
err_quit("usage: lat_sigwait <#loops>");
nloop = atoi(argv[1]);
Sigemptyset(&newmask);
Sigaddset(&newmask, SIGUSR1);
Sigprocmask(SIG_BLOCK, &newmask, NULL); /* block SIGUSR1 */
parentpid = getpid();
if ( (childpid = Fork()) == 0) {
for (i = 0; i < nloop; i++) { /* child */
Sigwait(&newmask, &signo);
Kill(parentpid, SIGUSR1);
}
exit(0);
}
/* 4parent */
Start_time();
for (i = 0; i < nloop; i++) {
Kill(childpid, SIGUSR1);
Sigwait(&newmask, &signo);
}
printf("latency: %.3f usec\n", Stop_time() / nloop);
exit(0);
}
void *SigThread(void *v)
{
int sig, n;
for (;;) {
Sigwait(&sigmask, &sig);
if (sig == SIGINT) {
for (n = 0; n < num_producers; ++n)
Pthread_cancel(producers[n]);
pthread_exit(NULL);
}
}
}
int
main(int argc, char **argv)
{
int signo;
mqd_t mqd;
void *buff;
ssize_t n;
sigset_t newmask;
struct mq_attr attr;
struct sigevent sigev;
if (argc != 2)
err_quit("usage: mqnotifysig4 <name>");
/* 4open queue, get attributes, allocate read buffer */
mqd = Mq_open(argv[1], O_RDONLY | O_NONBLOCK);
Mq_getattr(mqd, &attr);
buff = Malloc(attr.mq_msgsize);
Sigemptyset(&newmask);
Sigaddset(&newmask, SIGUSR1);
Sigprocmask(SIG_BLOCK, &newmask, NULL); /* block SIGUSR1 */
/* 4establish signal handler, enable notification */
sigev.sigev_notify = SIGEV_SIGNAL;
sigev.sigev_signo = SIGUSR1;
Mq_notify(mqd, &sigev);
for ( ; ; ) {
Sigwait(&newmask, &signo);
if (signo == SIGUSR1) {
Mq_notify(mqd, &sigev); /* reregister first */
while ( (n = mq_receive(mqd, buff, attr.mq_msgsize, NULL)) >= 0) {
printf("read %ld bytes\n", (long) n);
}
if (errno != EAGAIN)
err_sys("mq_receive error");
}
}
exit(0);
}
int main(int argc, char **argv)
{
int signo;
mqd_t mqd;
void *buff;
ssize_t n;
sigset_t newmask;
struct mq_attr attr;
struct sigevent sigev;
if (argc != 2)
err_quit("Usage: mqnotifysig4 <name>");
mqd = Mq_open(argv[1], O_RDONLY | O_NONBLOCK);
Mq_getattr(mqd, &attr);
buff = (void *)Malloc(attr.mq_msgsize);
Sigemptyset(&newmask);
Sigaddset(&newmask, SIGUSR1);
Sigprocmask(SIG_BLOCK, &newmask, NULL);
sigev.sigev_notify = SIGEV_SIGNAL;
sigev.sigev_signo = SIGUSR1;
Mq_notify(mqd, &sigev);
for ( ; ; )
{
Sigwait(&newmask, &signo);
if (signo == SIGUSR1)
{
Mq_notify(mqd, &sigev);
while ((n = mq_receive(mqd, buff, attr.mq_msgsize, NULL)) >= 0)
printf("read %ld bytes\n", (long)n);
if (errno != EAGAIN)
err_sys("mq_receive error");
}
}
exit(0);
}
