如何将光标锁定在Linux上的窗口内部？

I'm trying to put together a game for Linux which involves a lot of fast action and flinging around of the mouse cursor. If the user wants to play in windowed mode, I'd quite like to lock the cursor to the inside of the window to avoid accidentally changing programs in the heat of battle (obviously this will cancel itself if the user changes programs or hits escape for the pause menu.)I'm trying to put together a game for Linux whi