On input, a bufferevent does not invoke the user read callback unless
there is at least low watermark data in the buffer. If the read buffer
is beyond the high watermark, the bufferevent stops reading from the network.
On output, the user write callback is invoked whenever the buffered data
falls below the low watermark. Filters that write to this bufev will try
not to write more bytes to this buffer than the high watermark would allow,
except when flushing.
@param bufev the bufferevent to be modified
@param events EV_READ, EV_WRITE or both
@param lowmark the lower watermark to set
@param highmark the high watermark to set
Sets the watermarks for read and write events.
On input, a bufferevent does not invoke the user read callback unless there is at least low watermark data in the buffer. If the read buffer is beyond the high watermark, the bufferevent stops reading from the network.
On output, the user write callback is invoked whenever the buffered data falls below the low watermark. Filters that write to this bufev will try not to write more bytes to this buffer than the high watermark would allow, except when flushing.
@param bufev the bufferevent to be modified @param events EV_READ, EV_WRITE or both @param lowmark the lower watermark to set @param highmark the high watermark to set