x11

I'm trying to figure out how to take a screenshot of a window that is currently not focused, so there is a good chance that the window will be partially or fully obscured by other windows. I've found an example here on this link Get a screenshot of a window that is cover or not visible or minimized with Xcomposite extension for X11 but I can't make it work, any time I take a screenshot I get only strange output, mostly black, like I'm accessing the wrong buffer or something. XID xid = windowID; // Checked and confirmed that the window ID is correct XGetWindowAttributes( display, windowID,

I write automated tests for a website. One of the tests needs to press Ctrl + S and type some letters to save a webpage including CSS/JS. The test should require Firefox to have window focus for those several seconds to be able to type the filename and click "Save" (currently XDoTool is used for pressing keys and clicking the mouse). Sometimes I run the tests on my computer. I don't want to occasionally type something or change the window focus while the page is being saved, so I want to prohibit changing focus for those several seconds when those mouse clicks/key presses are running. It's not

My question is: is there a way to set up a virtual display as default display on a linux server (so that all GUI application launched will be displayed on that display, if no counter indication is made)? I tried using this: xvfb-run java -jar autoclick.jar , which produces the following output : searching graphic devices is Headless:false screen N°1 width:1600 height:900 just 1 robot click: Magic button clicked ! and here's the autoclick code : System.out.println("searching graphic devices"); System.out.println("is Headless:"+GraphicsEnvironment.isHeadless()); GraphicsEnvironment ge =