title: concurrent threads in C programming
body: <p>I have encountered a problem while implementing wait and signal conditions on multiple threads.</p>
  
  <p>A thread needs to lock a mutex and wait on a condition variable until some other thread signals it. In the meanwhile, another thread locks the same mutex and waits on the same condition variable. Now, the thread which is running concurrently throughout the process signals the condition variable but I want only the first thread that is waiting must be signalled and not the others.</p>