title: How to cancel a pending signal?
body: <p>How can I cancel a sent signal to a process which is still not delivered?</p>
  
  <p>Consider the scenario where I have sent a signal to a process, but the process was in un-interruptible state.</p>
  
  <p>I am doing a conditional wait for the signal to be handled. But since it did not I want to continue executing further. In that case, is there a way that I can cancel the sent signal(it is not yet delivered)</p>