4 ms·

Ah yes, I have fond memories of writing TSR pranks that hooked common DOS interrupts (not technically viruses since they didn't infect/replicate) that did thing

Ah yes, I have fond memories of writing TSR pranks that hooked common DOS interrupts (not technically viruses since they didn't infect/replicate) that did things like: 1) buffer 1 keystroke in memory (so typing diw<backspace>r would leave "di" on screen - then they'd type "r" and get an "r" and then hit enter and get another "r", then they'd hit backspace to correct the "dirr" and the command would execute, etc) 2) hooked the printer interrupt to introduce typos in printouts 3) randomly swap letters on the screen periodically Fun times. It's probably for the best that I grew up in the era that I did since pulling pranks like these has a high risk of getting slapped with felony charges in this day and age.

kazinator 8y ago
I played a prank of this type in some Unix C code that was homework for some third or fourth year networking or operating systems class. The executable forked off a prank process which simulated the effect of the professor doing a write to the teaching assistant's TTY. The fake professor's console message claimed that he happens to be looking at the same homework, which looks quite good and deserves a solid 19/20. And so when I got this back, the mark was 19/20 with a note saying "Well, <profname> told me to". Haha!
gesman 8y ago
When I was young I build small TSR .com (DOS exec extension) thing to instantly switch screen from game playing mode to serious work-BS mode with hotkey - at a first sign of boss approaching.
- gattilorenz 8y ago
  Ah, the good old "boss key" present in so many games! I remember it from Leisure Suit Larry [1], and a few more. At the time it was more like a "mom key" :) The open office was probably invented as a countermeasure for the boss key. [1] https://www.mobygames.com/game/leisure-suit-larry-goes-looking-for-love-in-several-wrong-places/screenshots/gameShotId,57500/ https://www.mobygames.com/game/leisure-suit-larry-goes-looki...
heyjudy 8y ago
Randomly transpose keys }:> Random error messages Reboot randomly Create unusual files And yet the antivirus can't find anything. :) BBS lists, Turbo Debugger and that giant purple & white Microsoft Press book with most of the Int 21h calls. Undocumented DOS, Undoc PC and Abrash's books were also helpful. Later, there were good free resources. Yeah, DOS viruses were bad: booting off an infected floppy, infected HD or running untrusted code was all it took. In Windows, it was worse because autorun would run untrusted code automatically without warning. There were some darn useful TSR's like Super PC-kwik Power Pak, QEMM and Desqview. Stacker and Doublespace/DriveSpace were kinda slow but did (mostly) work. Stacker had an accelerator card IIRC. And a commercial white bag/gray box mod for Welltris, Mouse Commander, added mouse support to Welltris for DOS by doing some mouse driver to keyboard translation in a TSR that was loaded and unload in a wrapper .BAT file. Many trainers, no-cd/runtime cracks and cheats also used TSR tricks to run.
- mickeyp 8y ago
  Qemm was essential. Not only did it hook CTRL+ALT+DEL to skip the POST BIOS check, making reboots faster, but it made it possible to shunt stuff out of convential memory into extended memory, making it possible to run games whilst having various drivers and so forth loaded. Qemm was the single best thing that ever happened to DOS-using me. The second best was Windows 95.
amenghra 8y ago
2) reminds me of http://web.kellegous.com/scratch/2003/printers1KBXB/ http://web.kellegous.com/scratch/2003/printers1KBXB/ where a printer proxy is used to create wavy text.
mickeyp 8y ago
Writing TSRs were the holy grail for me back in the day. I cut my teeth on Turbo C and even to this day I fondly remember hacking around with them. The first thing I did when I got internet access in 1996 was look up information on how how to write TSRs (oh, and stuff about X-Files) as I did not have access to any books on the subject.

kazinator 8y ago

I played a prank of this type in some Unix C code that was homework for some third or fourth year networking or operating systems class. The executable forked off a prank process which simulated the effect of the professor doing a write to the teaching assistant's TTY. The fake professor's console message claimed that he happens to be looking at the same homework, which looks quite good and deserves a solid 19/20. And so when I got this back, the mark was 19/20 with a note saying "Well, <profname> told me to". Haha!

gesman 8y ago

When I was young I build small TSR .com (DOS exec extension) thing to instantly switch screen from game playing mode to serious work-BS mode with hotkey - at a first sign of boss approaching.

gattilorenz 8y ago
Ah, the good old "boss key" present in so many games! I remember it from Leisure Suit Larry [1], and a few more. At the time it was more like a "mom key" :) The open office was probably invented as a countermeasure for the boss key. [1] https://www.mobygames.com/game/leisure-suit-larry-goes-looking-for-love-in-several-wrong-places/screenshots/gameShotId,57500/ https://www.mobygames.com/game/leisure-suit-larry-goes-looki...

heyjudy 8y ago

Randomly transpose keys }:> Random error messages Reboot randomly Create unusual files And yet the antivirus can't find anything. :) BBS lists, Turbo Debugger and that giant purple & white Microsoft Press book with most of the Int 21h calls. Undocumented DOS, Undoc PC and Abrash's books were also helpful. Later, there were good free resources. Yeah, DOS viruses were bad: booting off an infected floppy, infected HD or running untrusted code was all it took. In Windows, it was worse because autorun would run untrusted code automatically without warning. There were some darn useful TSR's like Super PC-kwik Power Pak, QEMM and Desqview. Stacker and Doublespace/DriveSpace were kinda slow but did (mostly) work. Stacker had an accelerator card IIRC. And a commercial white bag/gray box mod for Welltris, Mouse Commander, added mouse support to Welltris for DOS by doing some mouse driver to keyboard translation in a TSR that was loaded and unload in a wrapper .BAT file. Many trainers, no-cd/runtime cracks and cheats also used TSR tricks to run.

mickeyp 8y ago
Qemm was essential. Not only did it hook CTRL+ALT+DEL to skip the POST BIOS check, making reboots faster, but it made it possible to shunt stuff out of convential memory into extended memory, making it possible to run games whilst having various drivers and so forth loaded. Qemm was the single best thing that ever happened to DOS-using me. The second best was Windows 95.

amenghra 8y ago

2) reminds me of http://web.kellegous.com/scratch/2003/printers1KBXB/ http://web.kellegous.com/scratch/2003/printers1KBXB/ where a printer proxy is used to create wavy text.

mickeyp 8y ago

Writing TSRs were the holy grail for me back in the day. I cut my teeth on Turbo C and even to this day I fondly remember hacking around with them. The first thing I did when I got internet access in 1996 was look up information on how how to write TSRs (oh, and stuff about X-Files) as I did not have access to any books on the subject.