title: On the installation of mpi.h for C in Ubuntu
body: <p>I would like to start with MPI/C and I want to compile/execute the standard program mpi_hello.
  I succeeded regarding mpicc but I got an error message when I compile the file.
  Here is the program:</p>
  
  <pre><code>#include &lt;mpi.h&gt;
  #include &lt;stdio.h&gt;
  
  int main (int argc, char* argv[])
  
  {
  
  int mynode, totalnodes;
  
    MPI_Init(&amp;argc,&amp;argv);
    MPI_Comm_size(MPI_COMM_WORLD, &amp;totalnodes);
    MPI_Comm_rank(MPI_COMM_WORLD, &amp;mynode);
  
    printf( "\nHello world from process %d of %d\n", mynode, totalnodes );
    if(totalnodes==1) printf("You have just one processor!\n");
    MPI_Finalize();
    return 0;
  
  }
  </code></pre>
  
  <p>I got the following:</p>
  
  <pre><code>turb@turb-LIFEBOOK-AH531:~/Desktop/Prog$ mpicc mpi_hello.c
  turb@turb-LIFEBOOK-AH531:~/Desktop/Prog$ cc -O3 mpi_hello.c
  mpi_hello.c:6:17: fatal error: mpi.h: No such file or directory
   #include &lt;mpi.h&gt;
                   ^
  compilation terminated.
  </code></pre>
  
  <p>I would appreciate your help. Thank you!
  a</p>