Xorg X-Windows X11R7
Capture screen shot of the current window
This works on `xterm` and `gnome-terminal`. It should work on any terminal that defines WINDOWID.
xwd -id $WINDOWID -silent | xwud
This is similar but saves output to a PNG file.
xwd -id $WINDOWID -silent | xwdtopnm | pnmtopng > terminal_screenshot.png
Get background color of shell
This was motivated by the desire to have Vim start with the best color scheme depending on whether the terminal has a dark background or light background. It's sort of a ridiculous thing to do, but Xterm will not report its background color.
This is a hack. I'm still working on this.
This is the fastest way I found to guess the background color of a given window. This should give average color, but it seems to be more like median.
time xwd -silent -nobdrs -id $WINDOWID | convert - -gravity center -crop 1x1+0+0 -depth 8 txt:-
Average color, Slower:
time xwd -silent -nobdrs -id $WINDOWID | convert - -colors 1 -crop 1x1+0+0 -depth 8 txt:-
This makes a Desktop icon of a window:
time xwd -silent -nobdrs -id $WINDOWID | convert - -crop 32x32+0+0 -depth 8 xpm:-
Display apps on remote X11 desktop
If you xserver was started to listen to TCP port 6000 then this will work. If your Xorg was started with the -nolisten option then this will not work. Note that running your X server this way is very insecure. This is the old-fashioned way of doing it. This was invented before they invented security.
On your server you need to allow clients to connect to your display. From a command-line run this command:
On your client machine simply set your DISPLAY to the IP address of the server and then run your X app.
export DISPLAY=192.168.1.2:0.0 xclock