* Compilers that use an older prototype for recvfrom() will
	 * warn about the type of the sixth parameter, fromlen.  It
	 * is now standardized as unsigned, specifically as socklen_t.
	 */

(... but the code itself still uses unsigned int.  This comment was added
because HP/UX is complaining now even as other compilers stopped complaining
when it was changed from signed int to unsigned int.)