anchor.diff:  get_os_wordsize({unix, darwin})  -> get_os_wordsize_with_uname();
   get_os_wordsize({unix, netbsd})  -> get_os_wordsize_with_uname();
   get_os_wordsize({unix, freebsd}) -> get_os_wordsize_with_uname();
  +get_os_wordsize({unix, dragonfly}) -> get_os_wordsize_with_uname();
   get_os_wordsize({unix, openbsd}) -> get_os_wordsize_with_uname();
   get_os_wordsize(_)               -> unsupported_os.
   
  
positive.code:     PortMode = case OS of
  		   {unix, darwin} -> false;
  		   {unix, freebsd} -> false;
  		   % Linux supports this.
  		   {unix, linux} -> true;
  		   {unix, openbsd} -> true;
  
negative.code: 	    PortMode = case OS of
  			   {unix, darwin} -> false;
  			   {unix, freebsd} -> false;
  			   {unix, dragonfly} -> false;
  			   {unix, linux} -> false;
  			   {unix, openbsd} -> true;
  			   {unix, sunos} -> true;
  