DOS APPEND
Always a joy when os2museum updates.
I, too, remember the trifecta of APPEND, JOIN, and SUBST. And while I always thought they were interesting, I was also wondering for most of them when I would ever use that. At the time, DOS versions and hence applications for it that don’t know subdirectories didn’t cross my mind, as my first DOS version was 2.11, I think.
My favorite program in DOS was smartdrv.exe. I know it’s much more late addition, but it was a game-changer for these slow hard drives. Even a tiny cache size (I believe I tried kilobytes range) sped up things like 10-20x.
Even windows 3.x and 95 (surpisingly) ran faster with smartdrv preloaded. 95’s default cache for some reason was worse than smartdrv and literally produced harder sounds on my hdds.
The second favorite was a TSR NG viewer, can’t remember the name.
Another handy dos command, originating back to DOS is SUBST.
Came in pretty handy when I wanted to share a folder with Remote Desktop, but it would only let me select whole drives.
Made a SUBST drive letter for that folder, worked like a charm!
This is really neat!
Are there any good books on DOS that a person who enjoys articles like this may also enjoy?
And more broadly, does anyone have any good books to suggest about the personal computers of the 80s and 90s, that don't skimp on the messy technical details?
Is INT 2fH the DOS equivalent of PATH? What a bizarre mechanism, I've read it 2 times and I have no idea what it's saying lol:
I remember wondering APPEND as a kid three decades ago. Looks like it had a very specific legacy use case, which was no longer present in more modern DOS versions. Live and learn.
Huh. I knew this command existed but never looked into it. I assumed it was like cat, just appending files together.
> “In fact it is known that DOS 2.0 could not be built on PCs at all, and was built on DEC mainframes.”
Nitpick, but DEC never made a mainframe. Their products like the PDP-11 were considered minicomputers (even though the CPU was the size of a fridge) to distinguish them from IBM’s mainframes and medium sized computers.
> APPEND is one of the things that are completely irrelevant 99.99% of the time… yet can be extremely useful when the need arises.
Is it really that irrelevant? I mean, if you look past the specifics (directories, interrupts, DOS versions), this seems to be implementing the idea of bringing something into scope, in particular bringing it into scope from the outside, to modify the behavior of the consumer (here, assembler) without modifying the consumer itself. Today, we'd do the equivalent with `ln -sr ../../inc ../inc`.
I'd argue the general idea remains very important and useful today, though it's definitely not obvious looking back from the future what this was what APPEND was going for.