title: import function in c using extern keywod
body: <p>I am having problem with importing external function to a main c file.</p>
  
  <p>Here is my minimal code:</p>
  
  <pre><code>/* main.c */
  
  #include&lt;stdio.h&gt;
  extern int func() 
  
  int main(){
      extern int func();
  }
  
  /*external file with one function that I want to     
  import*/
  
  #include&lt;stdio.h&gt;
  
  int func(){
      printf("Hello World Again\n");
  }
  </code></pre>
  
  <p>I compile and run like this - <strong>gcc main.c</strong> and then <strong>./a.out</strong> but nothing is happening.
  Any idea ?</p>