linux usleep 测试

int usleep(useconds_t usec);

#include <stdio.h>
#include <unistd.h>

int main() {
    printf("开始暂停...\n");
    usleep(500000); // 暂停 500 毫秒
    printf("暂停结束。\n");
    return 0;
}

#include <time.h>

int nanosleep(const struct timespec *req, struct timespec *rem);

#include <stdio.h>
#include <time.h>

void precise_sleep(long seconds, long nanoseconds) {
    struct timespec start, current;
    clock_gettime(CLOCK_MONOTONIC, &start);
    while (1) {
        clock_gettime(CLOCK_MONOTONIC, &current);
        if ((current.tv_sec - start.tv_sec) > seconds ||
            (current.tv_sec == start.tv_sec && current.tv_nsec >= start.tv_nsec + nanoseconds)) {
            break;
        }
    }
}

int main() {
    printf("开始暂停...\n");
    precise_sleep(0, 500000000); // 暂停 500 毫秒
    printf("暂停结束。\n");
    return 0;
}