Thread initialization for multi-threaded clients. Multi-threaded clients should call mysql_thread_init() at the beginning of the thread initialization to initialize thread specific client library variables. If mysql_thread_init() was not called explicitly, it will be called automatically by mysql_init() or mysql_real_connect().
Returns zero if successful or 1 if an error occurred.
Before a client thread ends the mysql_thread_end() function must be called to release memory - otherwise the client library will report an error.
This function has been deprecated since MariaDB Connector/C 3.0.0.
