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启用compiz和fglrx时的vnc问题 | Problem of vnc server with compiz and fglrx enabled

困扰了我近两年的问题。

远程连vnc回我的电脑，第一个画面能看到，鼠标也可以动，但是键盘按没反应，画面也不会再动。
一开始以为是网络问题，或者是设置了view only，但是本机上看，鼠标和键盘都得到了响应，所以只是屏幕刷新的问题。

这个问题我一直不知道原因。 但是最近新装的ubuntu，一开始是可以连得，没有问题，我还以为是更新了解决了这个问题。但是最近又不行了，我才开始想最近改了什么设置。 最后发现原来是启动了fglrx，关了radeon。 改回radeon后vnc又复活了。

于是查了一下， 果然是个bug，见https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/353126, 而且nvidia的闭源驱动也有这个问题，我以前是用的nvidia的卡，只是一直用它的驱动，所以没有发现这个问题。


A problem that has been bothering me for nearly two years.

So the problem is, when trying to remotely connect to the vnc server enabled on my computer, I can see only the first screenshot, without further update, the mouse pointer is moving, but keyboard events are not responded.
I thought at first this must be something wrong with the network, or maybe "view only" is set on the server, however on my computer I see that mouse and keyboard are working properly, so it's only the problem of screen updating.

I didn't know the reason all the time until now. Recently I have a new Ubuntu installed on my computer, in the first few days vnc server was working well, and I had thought that this problem had been solved in this new version of Ubuntu. However vnc failes again these days, and I begin trying to remember what I have changed in the system. In the end I found that I've enabled fglrx and disabled radeon. And vnc come back to alive after switching back to radeon.

Later I found that it's indeed a bug, see https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/353126, which also affects the nvidia proprietary driver. I was using nvidia cards before, but I had always been using its proprietary driver, and that's why I didn't find the cause before.
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