Question

I want to create a timer using timerfd_create, but i don’t know how to check for the expiry.

Can someone please help me with an easy example?

I know how to create and populate using the settime as you can see from my earlier timer questions, but how to check the expiry of timerfd_create? I know it notifies via file descriptor of it’s expiry. But how to check it?

Thanks in advance.

Answer 1

You can use select or epoll to monitor the file descriptor. Here’s an example:

struct epoll_event event;
efd = epoll_create(2);

event.data.fd = timer_fd;
event.events = EPOLLIN;
epoll_ctl(efd, EPOLL_CTL_ADD, timer_fd, &event);

while (1) {
    struct epoll_event revent;
    epoll_wait(efd, &revent, 1, -1);
    /* revent can now be used */
}