Re: [alsa-devel] [PATCH] test/pcm-multi-thread: Remove pthread_cancel, add snd_pcm_close

David Henningsson wrote:

2. It is good practice to close pcm after usage

[...] for (i = 0; i < num_threads; i++) { if (pthread_create(&peeper_threads[i], NULL, peeper, (void *)(long)i)) { fprintf(stderr, "pthread_create error\n");

• 	snd_pcm_close(pcm);
  return 1;
  

  } }

Any previously created threads are already running. Calling some snd_* function on an already-closed device is worse than letting the OS clean up after the program exits.

If we'd wanted to be strictly correct, we would have to send a message to the threads and wait for them to exit (as the cleanup code below already does).

running = 0;

This variable should be volatile.

• for (i = 0; i < num_threads; i++)

• pthread_cancel(peeper_threads[i]);
  

  for (i = 0; i < num_threads; i++) pthread_join(peeper_threads[i], NULL);

Regards, Clemens