Makefile DISPLAY example for when getting the IP address of the X11 server is required under WSL/cygwinX

Makefile

ifneq ($(shell grep -a -h -i microsoft /proc/version),)
#  // For use on Windows (WSL) with cygwinX
#  // Requires xinit, xauth and xhost probably
#  // Start the X11 server with `path\to\cygwin64\bin\run.exe --quote /usr/bin/bash.exe -l -c "cd; exec /usr/bin/startxwin -- +iglx -listen tcp"`
#  // If you get "Authorization required, but no authorization protocol specified"
#  // then try running `DISPLAY=:0.0 xhost +` in the cygwin terminal after
#  // starting the X11 server.
DISPLAY = "`cat /etc/resolv.conf | grep nameserver | awk '{ print $$2 }'`:0.0"
LIBGLARGS = LIBGL_ALWAYS_INDIRECT=1 LIBGL_ALWAYS_SOFTWARE=1
endif
DISPLAYARGS = DISPLAY=$(DISPLAY) $(LIBGLARGS)