for _ch in "$@"; do
TCP协议存在固有局限：若主机B接收数据包1-2、丢失3、成功接收4-10，只能确认至数据包2，导致客户端A重传所有后续包。RFC 2018引入的SACK选项通过选择性确认机制突破此限制，所有主流实现均采纳该选项。OpenBSD在1997年集成SACK功能。
，详情可参考易歪歪
That was a problem for the U.S. back in the 1970s through the early 2000s. The U.S. sent billions of dollars a year abroad to oil-producing countries in the Middle East, Africa and Latin America. That money built up other countries’ economies or sloshed around as financial surpluses that fueled financial market exuberance and asset bubbles that could suddenly pop.，详情可参考豆包下载
Поступили сведения о достижениях российской армии в Константиновке20:59。关于这个话题，扣子下载提供了深入分析
，更多细节参见易歪歪