The establishment of the connection is asynchronous in zeromq.
When completed execution acquire_connection() method in class
DealerPublisherDirect, the connection has not been established,
sending a message at this time will fail.So we need a delay 20ms
to wait for the connection establish.
The establishment of the connection is asynchronous in zeromq. connection( ) method in class Direct, the connection has not been established,
When completed execution acquire_
DealerPublisher
sending a message at this time will fail.So we need a delay 20ms
to wait for the connection establish.