SecureCRT作為著名的SSH客戶端，經常用於登陸遠端伺服器。在上面編輯文字，特別是用vi開啟兩個文字，並且需要切換時，很容易出現卡死的現象，不能接受任何的鍵盤輸入。很是鬱悶。以前每次遇到這個問題，我只有關掉那個session重新開啟一個。這次又遇上，是在不能忍，試著解決一下。

仔細觀察會發現，在vi下切換文字“ctrl+w+w”時，很容易輸入成”ctrl+s”。隨便拿一個session試試就發現，果然是ctrl+s在作怪。只要輸入這個，就會卡死。搜尋了一下，發現果然是有原因的:

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, 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.

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, 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.ctrl+s是一個古老的shell控制鍵，在輸入ctrl+q就可以恢復了

被這個問題困擾好幾次了，CTRL+S,CTRL+Q，很好，以後就不需要重新開一個了。