does signal handler code block the main process?

Question

I am registering an alarm signal handler as follows and an alarm signal is set every second.

  sigact.sa_handler = time_handler;
  sigemptyset(&sigact.sa_mask);
  sigact.sa_flags = SA_RESTART;
  if (sigaction(SIGALRM, &sigact, NULL) < 0)
      panic("sigaction SIGALRM: %s\n", strerror(errno));

  /* Set alarm signal every second */
  alarm(1);

My question is does the function time_handler follow a separate execution path like a thread or does it block the main process.

Possible duplicate of http://stackoverflow.com/questions/6129927/issue-with-timer-with-long-signal-handler-sigalarm?rq=1 — DoxyLover, Jun 23 '14 at 22:28

score 0 · Answer 1 · answered Jun 25 '14 at 08:09

0

You can find out if you are using GNU C by adding a sleep() call in the callback, and seeing if the code afterwards is delayed.

answered Jun 25 '14 at 08:09

Marco Scannadinari

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does signal handler code block the main process?

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