I get this when I try to run hack as non-root:
perm: Permission denied
Cannot link safelock to perm
It seems you don't have write permission here.
Updated by jerome over 7 years ago
It's because the permissions on the hack directory (/var/games/hackdir, owned by root) are 770, which is a problem as it contains different files that the game will want to access (then impossible for non-root). But for two other games of /var/games, larn and phantasia, permissions are 775 ; I suppose it should have been the same for hack (but I can't find where hack is given its permissions).