title: simple XOR algorithm
body: <p>Although I've used C++ a lot, I'm struggling with the C differences (mainly in strings).</p>
  
  <p>Could you please show me a simple single function that encrypts a message with a key using XOR comparison.</p>
  
  <p>Thank-you </p>
  
  <p>EDIT:
  Both the key and the message are char*</p>