MS-DOS Executable

[Vyacheslav]

This works on all 32-bit versions of Windows... sorry 64-bit users. Pretty neat file manager

ftp://ftp.cs.umu.se/pc/msdosexe.zip

[mediate]

... aside from the obvious nostalgia of using such a program and remembering the old order when you needed something like this ... why would you use it?

On a side note, it is totally awesome. Very efficient file manager. Unfortunately, it can't display the sys32 folder in windows 7 ... it "doesn't have enough memory" even though I have 4 GB of ram + another 8 GB swap ... w/e. Awesome file manager.

[Vyacheslav]

I'm amazed that if you go to Special and End Session, it'll log you off.

[smartalco]

... aside from the obvious nostalgia of using such a program and remembering the old order when you needed something like this ... why would you use it?

On a side note, it is totally awesome. Very efficient file manager. Unfortunately, it can't display the sys32 folder in windows 7 ... it "doesn't have enough memory" even though I have 4 GB of ram + another 8 GB swap ... w/e. Awesome file manager.

I think (could be totally wrong) that MS-DOS is actually 16-bit, therefore only giving it access to 65kB of your RAM. Really depends on how this executable was made though. Any recent windows OS can't natively run 16-bit programs, so obviously this was restructured somehow, I just don't know if it was recompiled for 32-bit or if there is some sort of wrapper around it that makes it appear as a 32-bit app to the OS even though it is still running under the 16-bit assumption underneath.

[Vyacheslav]

DOS is 16 bit, so you are limited to 640k base memory and allowed up to 64mb expandable memory. About how NT versions of Windows handle 16-bit applications: see here:

http://en.wikipedia.org/wiki/Virtual_DOS_machine

[t̷s͢uk̕a͡t͜ư]

Okay, so I'm confused. Where does the number 640K come from? And how does a 16-bit architecture support upwards of 65 MB of RAM (if that's what you mean by "expandable memory")? I'm on the same page as smartalco here: 2^16 = 65536, or a hard limit of 64 KB of RAM.
...or are you just talking about these 32-bit "DOS extensions" mentioned in the Wikipedia article you linked?

[Vyacheslav]

This explains how extended memory and conventional memory work quite nicely.

http://en.wikipedia.org/wiki/Extended_memory

http://en.wikipedia.org/wiki/Conventional_memory

[t̷s͢uk̕a͡t͜ư]

I found this a bit more helpful, actually: http://en.wikipedia.org/wiki/X86_memory_segmentation
tl;dr: 80086's, 80088's, 80286's, and 80288's had a 4-bit segment register that was used for addressing, which improved the memory address range to 2^20 = 1 MB.