CTRL-S and CTRL-Q are called flow-control characters. They represent an antiquated way of stopping and restarting the flow of output from one device to another (e.g.， from the computer to your terminal) that was useful when the speed of such output was low. They are rather obsolete in these days of high-speed networks. In fact，原因其实是一样的。

under the latter conditions， 。

CTRL-S and CTRL-Q are basically a nuisance. The only thing you really need to know about them is that if your screen output becomes stuck， then you may have hit CTRL-S by accident. Type CTRL-Q to restart the output; any keys you may have hit in between will then take effect. 原来ctrl+s是shell控制键，网上看到crt远程使用vim的时候也是发现这个问题，在输入ctrl+q就可以恢复了，。