To slightly change my question: I used the reicast-joyconfig program to configure a gamepad. After I configured it, all of its buttons worked in Reicast. I rebooted, and Reicast still remembered my gamepad config. So I hoped I could locate where this configuration was saved, and that might be a clue as to where I can edit KB controls. I ran commands like "locate reicast | grep cfg" and "locate dreamcast | grep cfg", and after coming up with nothing that had been touched since the time I mapped the gamepad, I took out the greps to see if any other file had a name that sounds like it stores configurations, but no dice. I learned that /usr/local/share/reicast/mappings/ holds files for mapping various input devices, but none of them had been touched since I mapped the gamepad. Any ideas where else I can look, or how else I can search, to find out where my gamepad mapping is saved?