intfiction.org

Has anyone tried out "Inform School"? Rethorical question, really, lots of people must have. Well, I just wanted to know how seriously to take its introductory warning:



Crashing the Z-Machine? No problem, I can just kill the process. Lock up my computer? No-siree.

Ok, have there been ANY reports of this game actually locking up a computer? And anyway, how can it even do that from within a Z-Machine?

It's an old game... 1999? That was before most home computers had a real OS with real memory protection. "Very secure operating system" meant Unix or Linux, you know, those crazy nerd systems where a buggy interpreter *couldn't* take down other processes.

Amazing to think that we talk about 1999 as though it were last century (which it is!), it still feels like only last week.

So in a modern computer there's no danger of locking up the entire OS, right? Gotcha. I'll add a note to that effect in IFDB.

Wonder what'd happen in a mobile environment, though (if it could even run it)...

I believe the specific issue is if the game tries to write to a memory address outside the Z-machine's allocated range. (Most Inform games manage to avoid this, but Inform School allows the player to set up some crazy code constructions. This is what the author is warning you about.)

A good interpreter will check all game memory accesses, and throw a fatal error if anything is out of bounds. Early interpreters didn't always do this, because of the CPU cost of these constant checks. At this point all interpreters should do it. Even on mobile devices, which are (at this point) as powerful as 1999-era desktop machines, anyhow.

(I just looked at Glulxe, and realized that while I coded memory-access checking, it's turned off by default. That's embarrassing. Hopefully the binary distributions have been modifying the config... I'll change that next release.)

More people would have played it if it had a cooler name, like 'Inform School: OS Takedown'.

- Wade