DOS ain't dead

DOS kernel debugging (Announce)

posted by ecm  , Düsseldorf, Germany, 28.09.2025, 12:01

> Hello,
>
> while playing with the "boot" variant of Debug, I realized that the MS-DOS
> v7.1 kernel ( Win 98 SE ) can be convinced of not touching interrupt
> vectors 1 and 3 if signature "JP" is located at [CS:IP-2] of vector 1. Thus
> the debugger remains active until the cmd prompt appears.
>
> Is this some kind of "standard", also used by other DOS kernel variants?
> Found nothing about that in RBIL.

Thanks for writing about this. Added this signature to lDebug in https://hg.pushbx.org/ecm/ldebug/rev/a956b9211ac9

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l

Complete thread:

• DOS kernel debugging - Japheth, 29.04.2025, 05:14 (Announce)
  • DOS kernel debugging - ecm, 29.04.2025, 09:59
    • DOS kernel debugging - Japheth, 30.04.2025, 08:20
  • DOS kernel debugging - ecm, 28.09.2025, 12:01