Add in a recv() wrapper - comm_recv().

Add in a recv() wrapper - comm_recv().

From FreeBSD's recv/recvfrom:

     If from is non-nil, and the socket is not connection-oriented, the source
     address of the message is filled in.  Fromlen is a value-result parame-
     ter, initialized to the size of the buffer associated with from, and mod-
     ified on return to indicate the actual size of the address stored there.

.. so comm_recv() calls recv_from()