Questions tagged [ms-dos]
MS-DOS, the Microsoft Disk Operating System, its OEM-branded versions, and x86 DOS clones in general.
384 questions
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Was the second copy of the FAT ever used for anything?
As I remember, DOS had to update a backup copy of the FAT with each disk write, which I imagine would have greatly slowed write speed. Yet I don't recall any recovery software that used the second ...
- 4,783
16
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4
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Did DOS on the early, slow machines ever fail to handle interrupts timely, and what happened if it did?
DOS on the 8088 had to process interrupts and return. If a higher-priority interrupt occurred, the current handler was pushed and the higher-priority interrupt was serviced.
4.77 million seems like a ...
- 4,783
5
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0
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What's the advantage of replacing DOS/4GW with DOS/32A?
Introduction
As far as I understand, DOS/4GW was the thing that allowed most games from MS-DOS era to access beyond the 640KB conventional memory limit. (For completeness, there was also EMS and XMS, ...
- 151
3
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0
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Racing game running on DOS, for up to 4 players, each using a single key for input
I remember a funny DOS game, which I would like to play again.
It was able to be played by up to 4 people simultaneously. Each player had exactly 1 key on the keyboard. The only thing required for the ...
- 219
8
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3
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DOS program for 3D graphics
I occasionally find myself in the situation where I need to build a simple 3D image, and this DOS program I remember would come in very handy. I just cannot find it anywhere. I am not sure if it was ...
- 219
10
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2
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MS-DOS vector fractal generator?
I'm trying to remember the name of a DOS program I had in about 1990-1992. It used an iterated function system to generate fractal graphics with affine self-similarity, with the classic example being ...
- 409
5
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1
answer
305
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What's the maximum amount of sectors an LBA ROM-BIOS sector read call can access?
I recently added support for multi-sector CHS reads to an experimental fork of my kernel's initial loader, described in https://github.com/SvarDOS/bugz/issues/174
I have some space left before the ...
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10
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1
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Why it is that a 64-bit EXE file (PE64) can contain a custom MS-DOS stub (a MZ executable), but not a custom 32-bit Windows stub?
I think the question is self-explanatory. It's way more likely that somebody will accidentally try to run a PE64 executable under 32-bit Windows than that they will try to run it under DOS, so why ...
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11
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1
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In search of 86-DOS ttsr.h and corresponding library
I have returned to tweaking my port of WarpLink, a now public domain 8086 DOS OMF linker. (The ported files build with NASM and WarpLink itself. I run WarpLink using dosemu2 on our amd64 Debian server....
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7
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1
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434
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How to obtain error message text using MS-DOS interrupt 2Fh service 122Eh?
I'm trying to display error messages like a lot of MS-DOS (4.0+) utilities do. They don't embed messages like "Too many parameters" and "Invalid switch" in the executables, but ...
- 253
16
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1
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How is `SELECT` for MS-DOS 3.30 supposed to be used on 360KB floppy systems?
SELECT was the automatic installation program for MS-DOS 3 and later. SELECT on MS-DOS 3 was not interactive, and was supposed to be invoked with the following syntax:
SELECT [[sourceDrive:] ...
- 1,141
-4
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3
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Can Microsoft Windows 1.0 run on CPUs older than Intel 8086 with some software patches and hardware modifications? [closed]
Is there was any microprocessor older than Intel 8086 (e.g., Z80, Intel 8080) which can run The Microsoft Windows 1.0 and at least display the GUI without glitches?
Also, using software mods, binary ...
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1
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Is there a way to save the current path to a variable in a batch file in MS-DOS 6.0 without third-party tools?
Solutions such as
@ECHO OFF
SET MYPATH=%CD%
ECHO %MYPATH%
work in the CMD of Windows 10 and most likely also in earlier NT-based systems, but unfortunately they did not work in the COMMAND.COM of MS-...
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1
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2
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How could a program fault disable Ctl-Alt-Del on an 8088 / 286 / 386?
I remember sometimes the system would hang, and Ctl-Alt-Del didn't do anything. How could that happen?
Was it simply Application software stealing the keyboard interrupt vector from from the BIOS?
...
- 4,783
12
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1
answer
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What is the purpose of DPMI interrupt 31h function 300h?
In the DOS Protected Mode Interface, int 0x31 function 0x0300 is "Simulate Real Mode Interrupt". I found some documentation that says:
You may use this instead of the INT nn opcode to ...
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