zeromq/czmq — pull request #749 by hintjens (2014-10-20 14:14:10+00:00)
Title: Problem: zsock_recv 'm' assumes initialized message

This is inconsistent with all other picture formats and leads to
surprising code.

Solution: always initialize message before reading off socket.

If we need an "append to message" picture that should be a special
case, e.g. using 'M' as picture.