linux下的rtc测试程序

#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <linux/rtc.h>
#include <sys/ioctl.h>

void read_rtc_time(int fd) {
    struct rtc_time rtc_tm;
    if (ioctl(fd, RTC_RD_TIME, &rtc_tm) == -1) {
        perror("ioctl");
        return;
    }
    printf("Current RTC time: %04d-%02d-%02d %02d:%02d:%02d\n",
           rtc_tm.tm_year + 1900, rtc_tm.tm_mon + 1, rtc_tm.tm_mday,
           rtc_tm.tm_hour, rtc_tm.tm_min, rtc_tm.tm_sec);
}

void set_rtc_time(int fd, int year, int month, int day, int hour, int min, int sec) {
    struct rtc_time rtc_tm;
    rtc_tm.tm_year = year - 1900;
    rtc_tm.tm_mon = month - 1;
    rtc_tm.tm_mday = day;
    rtc_tm.tm_hour = hour;
    rtc_tm.tm_min = min;
    rtc_tm.tm_sec = sec;

    if (ioctl(fd, RTC_SET_TIME, &rtc_tm) == -1) {
        perror("ioctl");
        return;
    }
    printf("RTC time set successfully.\n");
}

int main() {
    int fd = open("/dev/rtc0", O_RDWR);
    if (fd == -1) {
        perror("open");
        return 1;
    }

    read_rtc_time(fd);

    // Example: Set RTC time to 2023-10-01 12:34:56
    set_rtc_time(fd, 2023, 10, 1, 12, 34, 56);

    close(fd);
    return 0;
}