Re: [gdm-list] Q: How to make screenshots/screencasts from a running gdm?

[Brian Cameron <Brian Cameron Sun COM>]

Mirco:

> 	An odd question to ask, I admit, but still I need some hints on this. I
> really want to make a screencast (or at least screenshots) of a running
> gdm... not just gdm running from inside a gnome-session (using
> DOING_GDM_DEVELOPMENT=1) or inside a Xephyr instance.
>
> Thanks in advance for your time and kind advice!

One way that might work would be to hack your /etc/X11/gdm/Init/Default
script so that it launches some program that allows you to take a
screenshot.  You would want to make sure it launches in the background
like this:

/usr/bin/screenshotprogram &

If you don't include the "&" at the end, then the Init script will hang
upon starting the program and not continue starting up until the
screenshot program exits.  Probably not what you want.

Not sure how well this would work, though.  gdmgreeter does not run with
a window manager, so if the screenshot program depends on a window
manager to hide itself, then this might not work so well.

Another approach might be to grab the Xauth cookie for the running GDM
and connect to it from another session to take the screenshot.  I'm not
sure exactly how you would do this, but it should allow you to get pixel
information for the running GDM windows.  The GDM docs explain where to
find the Xauth keys (though you need to be root to access them).

Brian