title: c++MPI instruction before all process started
body: <p>assuming i have code like this:</p>
  
  <pre><code>    int main(..){
              cout&lt;&lt;"something"&lt;&lt;endl;
              MPI_INIT(...);
              ..
              ..
              ..
              MPI_FINALIZE();
      }
  </code></pre>
  
  <p>I thought the cout before the init would be executed only once by the main process. Instead, it s executed as many times as the number of process. How can i run an instruction only one time and before that all process are started?</p>