title: how to give more than one c file as input to GNU Cflow?
body: <p>I was able to generate the callgraph of one file using gnu - cflow, but I was not able to find out how to generate the call graph for multiple files using cflow.</p>
  
  <p>I tried following </p>
  
  <ul>
  <li><p>cflow test.c,hello.c</p>
  
  <p>It generates the callgraph for test.c and not creating it for hello.c</p></li>
  <li><p>cflow test.c hello.c</p>
  
  <p>It generates the callgraph for hello.c and not creating it for test.c</p></li>
  </ul>
  
  <p>I don't know how to pass multiple files to cflow.</p>
  
  <p>Any idea about this?</p>
  
  <p>hello.c</p>
  
  <pre><code>int
   who_am_i (void)
   {
       struct passwd *pw;
       char *user = NULL;
  
       pw = getpwuid (geteuid ());
       if (pw)
       user = pw-&gt;pw_name;
       else if ((user = getenv ("USER")) == NULL)
       {
           fprintf (stderr, "I don't know!\n");
           return 1;
       }
       printf ("%s\n", user);
       unused_function();
       return 0;
   }
  
   int
   main (int argc, char **argv)
   {
       if (argc &gt; 1)
       {
           fprintf (stderr, "usage: whoami\n");
           return 1;
       }
       return who_am_i ();
   }
   void unused_function()
   {
       printf();
       error1();
       printf();
   }
   void error1()
   {
       error2();
   }
   void error2()
   {
  
   }
  </code></pre>
  
  <p>test.c</p>
  
  <pre><code>int tests()
  { return 0;}
  </code></pre>