title: Max line length in mail
body: <p>Why is the <a href="http://php.net/manual/en/function.mail.php" rel="noreferrer">php documentation of mail()</a> saying </p>
  
  <blockquote>
    <p>Lines should not be larger than 70 characters.</p>
  </blockquote>
  
  <p>(under the part: parameter message)?</p>
  
  <p>Is there an RFC specifying the line length of mails?</p>
  
  <p>This question: 
  <a href="https://stackoverflow.com/questions/9054708/php-mail-and-lines-should-not-be-larger-than-70-characters">PHP mail and Lines should not be larger than 70 characters</a> says</p>
  
  <blockquote>
    <p>there are not that many clients left that cannot deal with long lines</p>
  </blockquote>
  
  <p>So is it just bad build clients/servers that do bad stuff to too long lines,
  and 70 is a tested value that works well enough, or is there an RFC or something that
  says that mail-applications need to handle 70 char long lines?</p>