event_buffer_set_callback Set or reset callbacks for a buffered event &reftitle.description; boolevent_buffer_set_callback resourceevent mixedreadcb mixedwritecb mixederrorcb mixedarg Sets or changes existing callbacks for the buffered event. &reftitle.parameters; event Valid buffered event resource. readcb Callback to invoke where there is data to read, or NULL if no callback is desired. writecb Callback to invoke where the descriptor is ready for writing, or NULL if no callback is desired. errorcb Callback to invoke where there is an error on the descriptor, cannot be NULL. arg An argument that will be passed to each of the callbacks (optional). &reftitle.returnvalues; &return.success;