c - 如何用c语言在linux中创建定时器？

Question

我需要一个计时器，所以你能告诉我如何制作一个每毫秒都会中断我的计时器，然后我会有一个变量来计算毫秒数，然后每 20 毫秒我会调用主要功能？

Answer 1

如果没有其他事情可做，然后等待 20 毫秒，然后做一些事情，然后再次等待，以下方法可以：

#include <sys/time.h>
#include <sys/types.h>
#include <unistd.h>

int main()
{
  while (1)
  {
    struct timeval tv = {0, 20000}; /* 0 seconds, 20000 micro secs = 20 milli secs */

    if (-1 == select(0, NULL, NULL, NULL, &tv))
    {
      if (EINTR == errno)
      {
        continue; /* this means the process received a signal during waiting, just start over waiting. However this could lead to wait cycles >20ms and <40ms. */
      }

      perror("select()");
      exit(1);
    }

    /* do something every 20 ms */
  }

  return 0;
}