Are asynchronous operations supported?

[vcherkassky]

http://www.postgresql.org/docs/9.2/static/protocol-flow.html

46.2.6. Asynchronous Operations

There are several cases in which the backend will send messages that are not specifically prompted by the frontend's command stream. Frontends must be prepared to deal with these messages at any time, even when not engaged in a query. At minimum, one should check for these cases before beginning to read a query response.

[mairbek]

For now NoticeResponse, NotificationResponse and ParameterStatus messages are ignored and printing to output.