Sets the callback to be invoked when an error occurs.
public ul_ret_void ULSetErrorCallback( SQLCA * sqlca, ul_error_callback_fn_a callback, ul_void * user_data, char * buffer, size_t len )
sqlca A pointer to the SQLCA.
callback The callback function
user_data User context information passed to the callback.
buffer A user-supplied buffer that contains the error parameters when the callback is invoked.
len The size of the buffer in bytes.