Triggers the bufferevent to produce more data if possible.
@param bufev the bufferevent object
@param iotype either EV_READ or EV_WRITE or both.
@param mode either BEV_NORMAL or BEV_FLUSH or BEV_FINISHED
@return -1 on failure, 0 if no data was produces, 1 if data was produced
Triggers the bufferevent to produce more data if possible.
@param bufev the bufferevent object @param iotype either EV_READ or EV_WRITE or both. @param mode either BEV_NORMAL or BEV_FLUSH or BEV_FINISHED @return -1 on failure, 0 if no data was produces, 1 if data was produced