title: htonl without using network related headers
body: <p>We are writing an embedded application code and validating a string for a valid IPv4 format. I am successfully able to do so using string tokenizer but now I need to convert the integers to Host-To-Network order using htonl() function.</p>
  
  <p>Since it an embedded application I cannot include network header and library just to make use of htonl() function.</p>
  
  <p>Is there any way / non-network header in C++ by which I can avail htonl() functionality?</p>