Install xterm

[Jan Blechta]

xterm is useful for parallel debugging, e.g.: mpirun -n 3 xterm -e gdb -ex r -ex q -args python -B -m pytest -sv .

[Jack Hale]

We have to be careful not to end up with a container with the kitchen sink installed. I don't think this is core functionality and xterm can be installed in 2 seconds with apt-get.

[Jan Blechta]

I agree. It pulled 16.7 MB and took 159 MB disk. That's too much.

But this issue, although poorly formulated, was meant rather as a question how to use xterm from the container. Consider that

sudo apt-get update
sudo apt-get install -y xterm gdb
cd $FENICS_SRC_DIR/dolfin/build/test/unit/python/function
mpirun -n 3 xterm -e gdb -ex r -args python -B -m pytest -sv test_expression.py

fails with

xterm: Xt error: Can't open display: 
xterm: DISPLAY is not set
xterm: Xt error: Can't open display: 
xterm: DISPLAY is not set
xterm: Xt error: Can't open display: 
xterm: DISPLAY is not set

or just MWE

sudo apt-get update
sudo apt-get install xterm
xterm

Any ideas?

[Johannes Ring]

@blechta - See Use graphical applications on Linux hosts.

[Jan Blechta]

Wow, works like a charm, @johannes_ring

[Jack Hale]

As @johannes_ring says, X11 tunnelled out to the host works perfectly on Linux.

It is also possible on Mac OS X, but it doesn't work anywhere near as well so I don't include it in the official documentation.

http://kartoza.com/en/blog/how-to-run-a-linux-gui-application-on-osx-using-docker/