asn@gentoo ~/roms $ xmame -rp . mslug3
info: trying to parse: /usr/share/games/xmame/xmamerc
info: trying to parse: /home/asn/.xmame/xmamerc
info: trying to parse: /usr/share/games/xmame/xmame-SDLrc
info: trying to parse: /home/asn/.xmame/xmame-SDLrc
info: trying to parse: /usr/share/games/xmame/rc/mslug3rc
info: trying to parse: /home/asn/.xmame/rc/mslug3rc
loading rom 0: 256-sma.bin
loading rom 1: 256-p1.bin
loading rom 2: 256-p2.bin
loading rom 3: sfix.sfx
loading rom 4: sp-s2.sp1
loading rom 5: sm1.sm1
loading rom 6: 256-m1.bin
loading rom 7: 000-lo.lo
loading rom 8: 256-v1.bin
loading rom 9: 256-v2.bin
loading rom 10: 256-v3.bin
loading rom 11: 256-v4.bin
loading rom 12: 256-c1.bin
loading rom 13: 256-c2.bin
loading rom 14: 256-c3.bin
loading rom 15: 256-c4.bin
loading rom 16: 256-c5.bin
loading rom 17: 256-c6.bin
loading rom 18: 256-c7.bin
loading rom 19: 256-c8.bin
done
sfix.sfx     NOT FOUND
sp-s2.sp1    NOT FOUND
sm1.sm1      NOT FOUND
000-lo.lo    NOT FOUND
ERROR: required files are missing, the game cannot be run.