c - C中的usleep（）是否实现为忙等待？(Is usleep() in C implemented as busy wait?)

Question

I'm building a multithreaded application with pthreads and need a thread to periodically check some stuff.

(我正在使用pthreads构建多线程应用程序，并且需要一个线程来定期检查一些东西。)

During the time in between this thread shouldn't use any CPU.

(在此线程之间的时间内，不应使用任何CPU。)

Is this possible with usleep() ?

(usleep()有可能吗？)

Is usleep() not busy waiting?

(usleep()不忙于等待？)

Or is there a better solution?

(还是有更好的解决方案？)

  ask by zeebonk translate from so

Answer 1

The function usleep has been removed from SUSv4.

(usleep功能已从SUSv4中删除。)

You should probably use nanosleep instead or timers ( setitimer , etc).

(您可能应该使用nanosleep或计时器（ setitimer等）。)

As R.. notes in the comments, should the sleep be implemented as a busy wait:

(正如R ..在评论中指出的那样，应将睡眠实施为繁忙等待：)

• The thread would continue to use the CPU

  (线程将继续使用CPU)

• Other (lower-priority) threads wouldn't get a chance to run

  (其他（低优先级）线程将无法运行)

Thus:

(从而：)

• Some might use signals (I think SUSv3 mentioned SIGALARM?)

  (有些人可能会使用信号（我认为SUSv3提到了SIGALARM吗？）)

• Some might use fancy timers

  (有些人可能会使用花式计时器)