linux 定时器 模块

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <unistd.h>
#include <sys/timerfd.h>
#include <time.h>

void timer_handler(int fd) {
    uint64_t expirations;
    read(fd, &expirations, sizeof(expirations));
    printf("Timer expired %llu times\n", expirations);
}

int main() {
    int timer_fd = timerfd_create(CLOCK_MONOTONIC, 0);
    if (timer_fd == -1) {
        perror("timerfd_create");
        exit(EXIT_FAILURE);
    }

    struct itimerspec its;
    its.it_value.tv_sec = 1; // 初始定时器时间为1秒
    its.it_value.tv_nsec = 0;
    its.it_interval.tv_sec = 1; // 定时器间隔为1秒
    its.it_interval.tv_nsec = 0;

    if (timerfd_settime(timer_fd, 0, &its, NULL) == -1) {
        perror("timerfd_settime");
        exit(EXIT_FAILURE);
    }

    while (1) {
        timer_handler(timer_fd);
    }

    close(timer_fd);
    return 0;
}