+ /**
+ * Attempts to send some data from the given slice to the peer.
+ *
+ * Returns the amount of data which was sent, possibly 0 if the socket has since disconnected.
+ * Note that in the disconnected case, [`PeerManager::socket_disconnected`] must still be
+ * called and further write attempts may occur until that time.
+ *
+ * If the returned size is smaller than `data.len()`, a
+ * [`PeerManager::write_buffer_space_avail`] call must be made the next time more data can be
+ * written. Additionally, until a `send_data` event completes fully, no further
+ * [`PeerManager::read_event`] calls should be made for the same peer! Because this is to
+ * prevent denial-of-service issues, you should not read or buffer any data from the socket
+ * until then.
+ *
+ * If a [`PeerManager::read_event`] call on this descriptor had previously returned true
+ * (indicating that read events should be paused to prevent DoS in the send buffer),
+ * `resume_read` may be set indicating that read events on this descriptor should resume. A
+ * `resume_read` of false carries no meaning, and should not cause any action.
+ */