title: Disable Path MTU discovery on per socket on OS X
body: <p>Is there a way to disable Path MTU discovery on per socket basis on OS X?</p>
  
  <p><a href="https://stackoverflow.com/questions/973439/how-to-set-the-dont-fragment-df-flag-on-a-socket">This is how to set don't fragment bit on socket on Linux</a></p>
  
  <p>But <code>IP_MTU_DISCOVER</code> is not recognized on OS X.</p>
  
  <p>Only recognized options as per <code>netinet/in.h</code> on OS X are:</p>
  
  <pre><code>/*
   * Options for use with [gs]etsockopt at the IP level.
   * First word of comment is data type; bool is stored in int.
   */
  #define IP_OPTIONS      1    /* buf/ip_opts; set/get IP options */
  #define IP_HDRINCL      2    /* int; header is included with data */
  .....
  </code></pre>