int
main(int argc, char *argv[])
{
struct itimerspec ts;
struct timespec start, now;
int maxExp, fd, secs, nanosecs;
uint64_t numExp, totalExp;
ssize_t s;
if (argc < 2 || strcmp(argv[1], "--help") == 0)
usageErr("%s secs[/nsecs][:int-secs[/int-nsecs]] [max-exp]\n", argv[0]);
itimerspecFromStr(argv[1], &ts);
maxExp = (argc > 2) ? getInt(argv[2], GN_GT_0, "max-exp") : 1;
fd = timerfd_create(CLOCK_REALTIME, 0);
if (fd == -1)
errExit("timerfd_create");
if (timerfd_settime(fd, 0, &ts, NULL) == -1)
errExit("timerfd_settime");
if (clock_gettime(CLOCK_MONOTONIC, &start) == -1)
errExit("clock_gettime");
for (totalExp = 0; totalExp < maxExp;) {
/* Read number of expirations on the timer, and then display
time elapsed since timer was started, followed by number
of expirations read and total expirations so far. */
s = read(fd, &numExp, sizeof(uint64_t));
if (s != sizeof(uint64_t))
errExit("read");
totalExp += numExp;
if (clock_gettime(CLOCK_MONOTONIC, &now) == -1)
errExit("clock_gettime");
secs = now.tv_sec - start.tv_sec;
nanosecs = now.tv_nsec - start.tv_nsec;
if (nanosecs < 0) {
secs--;
nanosecs += 1000000000;
}
printf("%d.%03d: expirations read: %llu; total=%llu\n",
secs, (nanosecs + 500000) / 1000000,
(unsigned long long) numExp, (unsigned long long) totalExp);
}
exit(EXIT_SUCCESS);
}
int
main(int argc, char *argv[])
{
struct sigevent sev;
struct itimerspec ts;
timer_t *tidlist;
int s, j;
if (argc < 2)
usageErr("%s secs[/nsecs][:int-secs[/int-nsecs]]...\n", argv[0]);
tidlist = calloc(argc - 1, sizeof(timer_t));
if (tidlist == NULL)
errExit("malloc");
sev.sigev_notify = SIGEV_THREAD; /* Notify via thread */
sev.sigev_notify_function = threadFunc; /* Thread start function */
sev.sigev_notify_attributes = NULL;
/* Could be pointer to pthread_attr_t structure */
/* Create and start one timer for each command-line argument */
for (j = 0; j < argc - 1; j++) {
itimerspecFromStr(argv[j + 1], &ts);
sev.sigev_value.sival_ptr = &tidlist[j];
/* Passed as argument to threadFunc() */
if (timer_create(CLOCK_REALTIME, &sev, &tidlist[j]) == -1)
errExit("timer_create");
printf("Timer ID: %ld (%s)\n", (long) tidlist[j], argv[j + 1]);
if (timer_settime(tidlist[j], 0, &ts, NULL) == -1)
errExit("timer_settime");
}
/* The main thread waits on a condition variable that is signaled
on each invocation of the thread notification function. We
print a message so that the user can see that this occurred. */
s = pthread_mutex_lock(&mtx);
if (s != 0)
errExitEN(s, "pthread_mutex_lock");
for (;;) {
s = pthread_cond_wait(&cond, &mtx);
if (s != 0)
errExitEN(s, "pthread_cond_wait");
printf("main(): expireCnt = %d\n", expireCnt);
}
}
int
main(int argc, char *argv[])
{
struct itimerspec ts;
struct sigaction sa;
struct sigevent sev;
timer_t *tidlist;
int j;
if (argc < 2)
usageErr("%s secs[/nsecs][:int-secs[/int-nsecs]]...\n", argv[0]);
tidlist = calloc(argc - 1, sizeof(timer_t));
if (tidlist == NULL)
errExit("malloc");
/* Establish handler for notification signal */
sa.sa_flags = SA_SIGINFO;
sa.sa_sigaction = handler;
sigemptyset(&sa.sa_mask);
if (sigaction(TIMER_SIG, &sa, NULL) == -1)
errExit("sigaction");
/* Create and start one timer for each command-line argument */
sev.sigev_notify = SIGEV_SIGNAL; /* Notify via signal */
sev.sigev_signo = TIMER_SIG; /* Notify using this signal */
for (j = 0; j < argc - 1; j++) {
itimerspecFromStr(argv[j + 1], &ts);
sev.sigev_value.sival_ptr = &tidlist[j];
/* Allows handler to get ID of this timer */
if (timer_create(CLOCK_REALTIME, &sev, &tidlist[j]) == -1)
errExit("timer_create");
printf("Timer ID: %ld (%s)\n", (long) tidlist[j], argv[j + 1]);
if (timer_settime(tidlist[j], 0, &ts, NULL) == -1)
errExit("timer_settime");
}
for (;;) /* Wait for incoming timer signals */
pause();
}
