zeromq/libzmq — pull request #1258 by hintjens (2014-11-17 13:54:16+00:00)
Title: Problem: linger values other than -1 or 0 are unsafe

Solution: set defaults back to infinity, and add new context
option, ZMQ_BLOCKY that the user can set to false to get a
less surprising behavior on context termination. Eg.

zmq_ctx_set (ctx, ZMQ_BLOCKY, false);