linuxTCP数据包重传过程

于TCP/IP协议栈的TCP协议的重传功能是由在linux内核源码(net/ipv4/tcp_output linuxtcp.c)中的函数tcp_retransmit_skb()实现的 代码如下：  /* This retransmits one SKB.  Policy decisions and retransmit queue  * state updates are done by the caller.  Returns non-zero if an  * error occurred which