title: how to find if the machine is 32bit or 64bit
body: <p>Is there anyway from a C prog to find whether the OS is currently running in 32bit or 64bit mode. I am using a simple program as below</p>
  
  <pre><code>int main(void){
       switch(sizeof(void*)){
          case 4: printf("32\n");
          break;
          case 8: printf("64\n");
          break;
      }
  }
  </code></pre>
  
  <p>Is this a correct approach ?
  Would this code work in all the scenarios like, If the hardware is 64bit and the OS is 32bit what would it return ? I don't have machine to test this in diff configurations.</p>
  
  <p>Thanks for the advice.</p>