Non-Blocking Client Library
MariaDB client library (starting with version 5.5.21) and MySQL Connector/C (starting with version 2.1.0) supports non-blocking operations.
About Non-blocking Operation in the Client LibraryAn introduction to the non-blocking features of the client library.
Using the Non-blocking LibraryHow to use the non-blocking client library
Non-blocking API ReferenceA list of all functions in the non-blocking client API, and their parameters