title: Convert a NSString
body: <p>My situation is explained in the code below.
  I need to send via a socket NSString drawn from a TextBox</p>
  
  <p>Thank you very much</p>
  
  <pre><code>NSString *string = fieldTesto.txt;
  // I Find an istruction for insert s string in to the CFSocketSend
  UInt8 message[] = "Hello world";
  CFDataRef data = 
               CFDataCreate(NULL, message, sizeof(message));
  CFSocketSendData(s, NULL, data, 0);
  CFRelease(data);
  </code></pre>