Building xpilot classic on Ubunut 15.04

sudo apt-get install libx11-dev xutils-dev libxext-dev

Download xpilot classic from SourceForge, Unpack.

xmkmf -a
make

I got:

Error in textinterface.c: getline conflicts with builtin

Replace all occurences of 'getline' with 'getline2' in src/client/textinterface.c

Then make. Works!