os8088 v1.0.20260810
os8088 plays Infocom text adventures now. A new program called Frotz runs the story files those games were published as: Mini-Zork, Colossal Cave Adventure, Zork: The Undiscovered Underground and Photopia all work. It is 23,722 bytes of 8086 assembly.
Nothing in the system itself changed in this release, so the four images below are byte for byte the ones from v1.0.20260809. Frotz travels on a story floppy of its own, built from a source checkout.
Frotz plays Infocom games (#72)
Infocom wrote their games for a pretend computer called the Z-machine, and then wrote one small program per real computer to run it. That is why a story file from 1982 is still a plain file that still works.
Frotz is that small program, written for os8088 in 8086 assembly. It is 23,722 bytes and it handles every version of the format, 1 through 8. A story is held in memory whole while you play, so it checks the size before it reads anything and turns the job down with a number in it -- Anchorhead needs 508K and this machine has 149K free -- rather than failing part of the way in. Saved games are written in Quetzal, the format other interpreters use, so a game saved here can be finished on a laptop.
There is a page about it, with screenshots of four stories running and what it deliberately does not do: https://os8088.com/spotlight/frotz/
A floppy of its own, and no games in the repository (#72)
Frotz is not on the software disk. The 360KB disk has about 100KB free and the interpreter is most of that, never mind a game to play on it, so make zdisk builds a story floppy in all three sizes instead.
The story files are not in the source tree either -- they are other people's games. The build fetches each one and checks it against a recorded checksum, from a list limited to what the authors released freely. That is why the Infocom titles are Mini-Zork I, both Sampler disks and Zork: The Undiscovered Underground, and not Zork I to III or The Hitchhiker's Guide, which Activision still sells.
Before you download
The four images here are identical to the last release and Frotz is not on them. To play a story:
make zdisk
in a source checkout. That fetches the freely released games and writes the disk in all three sizes. Boot os8088 from the usual first floppy and put the story disk in as the second one.
Once it is running, open FROTZ.O88 first and then choose File > Open Story... to pick a game out of one of the folders. Double-clicking a story file only starts it when the file is in the root of the disk, and the disk make zdisk builds sorts its stories into folders by era.
Figures
| Kernel image | 80,486 bytes (unchanged) |
| Image + .bss | 55,355 of 65,536 (10,181 free) |
| Source | 152,837 lines of assembly across 34 kernel modules |
The source figure changed because the way it is counted changed, not because that much was written. It used to count each program's main file and stop there, which missed the other files four of them are mostly made of -- 37,309 lines across ArtfulType, the MOD player, the tracker and Frotz. The same tree under the old count is 115,528 lines, and the module count was one too many: there are 34.
Downloads with SHA-256 checksums: https://os8088.com/download/