DOS ain't dead

Announcement: KEEPHOOK (Announce)

posted by ecm  , Düsseldorf, Germany, 14.10.2021, 00:27

> > The manual contains a very detailed description of this technique. I'm
> > particularly interested in what you may think of "the long story" in the
> > manual.
>
> Interesting program. The concept reminds me a little bit of the old MARK
> and RELEASE programs from the TSRCOM35 package. It seems as though
> KEEPHOOK may only work with AMIS-compatible TSR's, though. Is that so, or
> would it help with uninstalling "regular" TSR's also?

A TSR's uninstaller needs to use the advanced deinstallation method to gain from KEEPHOOK handlers. Although that implies that the TSR itself is also an AMIS multiplexer, to be exact it doesn't actually have to be.

I may write a companion program (all transient) which re-orders interrupt handlers. This would be useable with TSRs that do not exploit AMIS, too. The difficult problem is that to bubble up a certain handler we need to be able to insert another handler into the chain behind the one to expose. This usually would require to detect the next handler pointer of the handler to expose, ie it needs to have an IISP header.

A different way may be possible by installing KEEPHOOK and covering the same interrupt twice: once before installing the TSR and once after. However, I'm not sure how to avoid loops or insure that the order of the handlers is correct.

> Over time I'm
> converting my TSR's to AMIS so it might come in handy for me, but I haven't
> completed that process yet.
>
> As far as "the long story" I think you did a pretty good job of explaining,
> but a little block diagram with some arrows may help. This stuff can be
> very confusing and even people who've written TSR's but aren't familiar
> with IISP or AMIS may have a hard time following it. I've tried writing
> explanations of things like this before and sometimes even I get confused
> with what I've written -- this is a hard thing to explain.

Thanks for the feedback. I may consider adding a diagram. I'd have to draw it with ASCII art though.

---
l

Complete thread:

• Announcement: KEEPHOOK - ecm, 12.10.2021, 18:54 (Announce)
  • Announcement: KEEPHOOK - ecm, 13.10.2021, 18:26
  • Announcement: KEEPHOOK - bretjohn, 13.10.2021, 21:24
    • Announcement: KEEPHOOK - ecm, 14.10.2021, 00:27
      • Announcement: KEEPHOOK - bretjohn, 14.10.2021, 00:55
        • Announcement: KEEPHOOK - ecm, 16.10.2021, 18:53
  • Announcement: KEEPHOOK - andrewbird, 17.10.2021, 18:30