title: How to Run one Process Twice with shell script?
body: <p>If I have an executable, what is the correct way to run it twice with shell script ?<br>
  The process to be executed twice is using shared memory for message passing and shared semaphores<br>
  using simply <br></p>
  
  <pre><code>./a
  ./a
  </code></pre>
  
  <p>will run one process and other process can't run until first process stops and therefore no communication between two processes takes place<br>
  what is the right way to run one executable twice in parallel fashion ?</p>