6 ## Read/Write/Error Callback:
7 * Input: `(bufferevent, what)`
8 * `bufferevent` - Reference to the bufferevent that raised the callback
9 * `what` - What happened:
10 * == `EVBUFFER_READ` - Buffer contains at least low-watermark length and no more than high-watermark length
11 * == `EVBUFFER_WRITE` - Buffer ready to write to
12 * (other) - Error condition
13 * May be or-ed/added with `EVBUFFER_READ`/`EVBUFFER_WRITE` to specify where it happened
14 * `EVBUFFER_ERROR` - Marks error condition (need to look at 'errno' for error.. not exposed yet)
15 * `EVBUFFER_TIMEOUT` - Marks activity timeout
16 * `EVBUFFER_EOF` - Marks disconnection/end-of-file condition
19 * Input: `(fd, read, write, error)`
20 * `fd` - File descriptor to watch
21 * `read` - (may be nil) - callback to call when data in buffer is above the low watermark
22 * `write` - (may be nil) - callback to call when the output buffer contains less data than the low watermark
23 * `error` - callback to call when there is an erroneous condition
26 * Releases the bufferevent
27 * Disconnects event buffers since they were owned by the bufferevent object in 'C' land
28 * Disconnects all references so that any erroneous callbacks don't cause failures