udp

监听指定地址.

NewKCP create a new kcp control object, 'conv' must equal in two endpoint from the same connection.

need to send IKCP_CMD_WASK.

need to send IKCP_CMD_WINS.

cmd: ack.

cmd: push data.

cmd: window probe (ask).

cmd: window size (tell).

7 secs to probe window size.

up to 120 secs to probe window.

normal min rto.

no delay min rto.

监听器的解包分发协程数量.

监听器的收到通道数量.

fec 序号收到的记录长度 需要大于 kcp的wnd_size.

fec 冗余册数 3 => p1(x1, x2, x3).

kcp的刷新间隔.

kcp输出的单个包的长度.

kcp的流控.

kcp的延迟发送.

kcP的重传次数.

kcp的update调用时间间隔.

kcp的窗口的大小.

监听器的初始容量.

单个udp包的最大包长，用于做缓存（ 必须 >= kcp_mtu + fec_head_Len）.

会话投递数据给logic的通道大小.

会话发送数据的通道大小.

会话接收socket数据的通道大小.

KCP defines a single KCP connection.

数据流 send2kcp: kcp=>fec=>socket recv2fec: socket=>fec=>kcp 缓存池流 recv: pop=>chSocket=>fec=>kcp=>push seg: pop=>new=>delete=>push unpack: pop=>unpack=>logic=>push.