title: Which line break in php mail header, \r\n or \n?
body: <p>I've seen a lot of examples using the php mail function. Some of them use \r\n as line break for the header, some use \n.</p>
  
  <pre><code>$headers = "From: Just Me\n"; 
  $headers .= "Reply-To:  Just me &lt;$email&gt;\n"; 
  </code></pre>
  
  <p>vs</p>
  
  <pre><code>$headers = "From: Just Me\r\n";
  $headers .= "Reply-To:  Just me &lt;$email&gt;\r\n";
  </code></pre>
  
  <p>which one is correct? </p>
  
  <p>Sometimes I've had cases where \r\n is used and part of the header is interpreted by some email clients as mail text (losing these header information) - is this because \r\n is wrong?</p>