Weird file extensions

A lot of downloads in the /idgames sections features zip files with not only the wads, but other unidentified files as well. I've commonly found files suffixes such as:

.DIZ
.COM
.BBS
.ORG
.NFO
.IT
.LOG
.SDI
.BWS
.1ST

What is all this stuff?

Welcome to the 80s/90s! With the exception of .COM and .IT, Most of these formats were simply plain text files (simple ".TXT" in modern parlance) with different extensions to indicate their purpose in the BBS/G-File era, rather than having them all ending with ".TXT"

From the top of my head:

.DIZ: usually only found as "ID.DIZ" or "FILE_ID.DIZ", it was a plaintext description of a zip archive's, usually duplicated inside and outside the archive itself, for the convenience of downloaders and for preview reasons. Some archive tools, even today, will display this file as a thumbnail of sorts when you open an archive that has contains it. They are often short (max 5-6 lines) and contain ASCII art.


.BBS: Basically a plaintext file usually found alongside a downloadable file for BBS indexing or "content preview" purposes. I remember this mostly from those old shareware CDs that had a large FILES.BBS file in each directory, listing a summary of what each of the zipped archives contained.

.LOG: textfiles containing loggable information, e.g. version revisions or they were simply created by running some program. Pretty common even in Windows and Unix nowadays.

.IT: I'm aware of that as a binary tracked music format. Much more rarely it may be a text file with IT standing for "InformaTion" or somesuch.

.COM: simpler type of DOS executable files, older than the most common .EXE format and limited to 64 KB (one segment). Usually were used to provide a self-executable text-file reader with colors/effects/scrolling etc. if you found them in the archives alongside larger programs with names such as "INTRO.COM" or "README.COM". Sometimes they were actual cracktros or full-fledged demoscene intros/minidemos with actual graphics/sound advertising a BBS. As with all executables, be wary before launching them, as some might still contain pretty bad stuff (viruses)...

.ORG/.NFO: usually "info" or distribution information. NFO is still used today by w4r3z d00dz. THere are even dedicated "NFO readers" that make sure that the funderful ASCII graphics usually contained therein render correctly in this modern, cruel, "web oriented" world ;-)

.BWS/.SDI: No consistent use that I can recall, I guess disk or directory information, or proprietary binary files.

.1ST: Usually as "README.1ST", aka "Readme First". A textfile asking that you read it first ;-)

Also, I wonder how you missed ".DOC", a very common extension for text files: these were plain text files in 99.999% of cases back in those days, and not Microsoft Word "doc" files. Trying opening one of those with Word today results in hilarity ;-)

Please note that a lot of Apogee games used FILE_ID.DIZ as a means of copy-protection. If you couldn't find the shareware version of a game and wanted to give a copy to a friend to try out, you could omit that file and the friend would only get to play a small part of the game (in DN2, that is the first stage of any episode).

My Vista still recognizes .NFO but errors before giving System Information. I guess it expects to find a fixed system font from the file?

bytor said:

My Vista still recognizes .NFO but errors before giving System Information. I guess it expects to find a fixed system font from the file?

I think .NFO was a saved system information file.

Microsoft claimed stake to the ".nfo" extension by assigning it to the System Information program (not unlike the ".doc" extension explained by Maes). Pretty much all *.nfo files you find, however, are just plain text files; open that with Notepad or some dedicated viewer (those typically map the CP437 box-drawing characters to actually display properly in modern environments).

bytor said:

My Vista still recognizes .NFO but errors before giving System Information. I guess it expects to find a fixed system font from the file?

The NFO extension is used by Microsoft to store system information dumps. If you use the save menu option in Win7's system information it prompts you for a file name and uses the NFO extension. Doing that on my system creates what I think is an xml file of 2.27MB and 19988 lines of text.


I think Maes is pretty much spot on with what he said. I certainly remember when most of those file names/extensions were in common use. I always thought, but never had it confirmed anywhere, that the DIZ extension might have stood for DIZcription. ;)

I almost posted some ASCII art in that "earliest internet experiences" thread. Alot of it has a .phr extension which IIRC was the extension used by a program that allowed multiple lines to be scrolled in chat rooms.

oh hell I got castles and animals and all kinds of stuff that I grabbed back in the 90s.

Enjay said:

The NFO extension is used by Microsoft to store system information dumps. If you use the save menu option in Win7's system information it prompts you for a file name and uses the NFO extension. Doing that on my system creates what I think is an xml file of 2.27MB and 19988 lines of text.


I think Maes is pretty much spot on with what he said. I certainly remember when most of those file names/extensions were in common use. I always thought, but never had it confirmed anywhere, that the DIZ extension might have stood for DIZcription. ;)

It stands for Discription in Zipfile, iirc.

It stands for Discription in Zipfile, iirc.

Yep.

http://en.wikipedia.org/wiki/FILE_ID.DIZ
http://en.wikipedia.org/wiki/.nfo

Microsoft has a long history of appropriating file extensions. Check out your .acs script files sometime. That honky-nosed dude showing up for an icon is related to the Office assistant system and dates somewhere back to around the days of Microsoft Bob 9_9

Quasar said:

Microsoft has a long history of appropriating file extensions. Check out your .acs script files sometime. That honky-nosed dude showing up for an icon is related to the Office assistant system and dates somewhere back to around the days of Microsoft Bob 9_9

I never really understood the need for "assistants". Even in MS circles, the technology was dubbed "Total Fucking Clown". Thankfully, the stupid thing isn't needed at all.

Maes said:

.DIZ: usually only found as "ID.DIZ" or "FILE_ID.DIZ", it was a plaintext description of a zip archive's, usually duplicated inside and outside the archive itself, for the convenience of downloaders and for preview reasons. Some archive tools, even today, will display this file as a thumbnail of sorts when you open an archive that has contains it. They are often short (max 5-6 lines) and contain ASCII art.

Actually that's only partially true. DIZ files were used extensively by the Amiga scene, and the containers were like 95% lha's, 5% lzx's.

qoncept said:

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

That nfoview program seems kinda bloated for something that can be easily done in UTF-8 console or uxterm:

alias kat='luit -g2 '\''CP 437'\'' -- cat'

What does the k mean? K-rad, or something. ;)

Edit: bah, looks like the forum software ate my backslashes (even though it's in CODE tags). Well, you can just read the luit man page, it's easy enough to figure out...

The point of packaging an nfo viewer was that you couldn't count on the clowns downloading your warez to open the file in anything other than notepad.

40oz said:

.BBS
.ORG
.IT
.SDI
.BWS

What is all this stuff?

.BBS can be a Bulletin Board tag file, so you know where the zip was downloaded from (best viewed using Terminal font).
The only .ORG file I found is a copy of the ENDOOM lump from Registered Doom, so I'd say in this case the suffix is short for Original.
.IT are plain text files (explain.it, justdo.it & howtorun.it).
.SDI is a FidoNet Software Distribution Network Info file, a plain text format.
LEV1_1.BWS is a PWAD with an oddball suffix from Brian's World BBS.

Some of these are obviously non-standard suffixes.

Porsche Monty said:

Actually that's only partially true. DIZ files were used extensively by the Amiga scene, and the containers were like 95% lha's, 5% lzx's.

Tru dat, LZ?*LH* were the standard for Aminet and other Amiga-oriented file archive, though I never really paid attention whether they contained .DIZ files or not.

Speaking of Amiga and extensions, WTF was up with the habit of prefixing extensions in Amiga archives? E.g. module files would be named "mod.axelf" instead of "axelf.mod" (ok, extensions were generally not used much outside of MS-DOS anyway, but still)

Maes said:

Speaking of Amiga and extensions, WTF was up with the habit of prefixing extensions in Amiga archives? E.g. module files would be named "mod.axelf" instead of "axelf.mod" (ok, extensions were generally not used much outside of MS-DOS anyway, but still)

Amiga OS didn't make use of file extensions. People used them as prefixes to sort their files by type.

Gez said:

Amiga OS didn't make use of file extensions.

AFAIK, file extensions were only ever meaningful (and even necessary) to the OS itself in CP/M, in some BASIC intepreters, and CP/Ms later, most distant derivatives, including MS-DOS and eventually Windows.

E.g. BASIC-powered homecomputers would save ".BAS" files to disk, while most other stuff would be ".BIN" or ".DAT". MSX and the Sharp X68000 had ".EXE" files too.

On the converse, in the UNIX world and most other major OSes (including Mac OS and Amiga OS), file extensions were almost never meaningful, in particular for marking a file as executable.

But extensions are useful for users as a way to quickly know what files are supposed to be when looking at a listing, or to do stuff like dir *.txt. So even systems where they're not required tended to end up with them, and given the one-dimensional nature of a name, they can only be glued at the end (like DOS) or the beginning (like AmigaOS).

Nowadays we'd do that with tons of metadata in the file system, but back people were finding out that 640kb wasn't actually enough for everyone and they tried to keep it lightweight.

.nfo is always a burden when clikcing goes to fast.
Remember it from Skidrow and co.

As far as filename extensions go, even current versions of Windows don't strictly need them. The "." in a filename has no special meaning and to the file system, an extension is just as meaningful (not at all) as it is on Unix. Likewise, ".exe" for executables isn't strictly required and it's not that hard to launch applications without a ".exe" extension (though Windows Explorer doesn't do it); just like Unix, NTFS has an executable flag that really tells whether a file is allowed to be executed (and removing the flag from *.exe files makes them unrunnable, too :P)

Windows, however, does do a lot of pretending that file extensions are meaningful, especially in the context of Windows Explorer where it's nearly impossible to use a file in any useful way unless it has a proper extension attached to the name. Most applications don't care, but Windows Explorer is particularly obtuse about it. Mainly for DOS compatibility, they also go out of the way to pretend that "." is still a special character on the file system level, by making it impossible to create files that begin or end in a period with the name, even though the normal file-creation APIs don't have anything against it.

I particularly dislike how you can't really associate "no extension" with a default action in Windows. Makes opening all those unix-style text files like "README", "CHANGES" and "Makefile" a chore.

That stuff about .exe not being really required to launch makes some sense, but Windows has to deal with at least 3 file systems (FAT, FAT32 and NTFS as well as the various UDF/CDFS stuff) not all of which really support proper file metadata.

You can "launch" certain kind of files even from the command line, but that's really only taps into the file associations in the registry, e.g. "running" a .txt file will open notepad, "running" a .jar file will call Java (actually, that's desirable) etc.

However, you can force execution of any file (as long as its contents are a proper binary executable) with the cmd.exe tool. It will execute any file passed as parameter, as long as its internal signatures/header match a type of executable that the CreateProcess function of the Windows NT API can handle.

DOS was far less scrupulous: it would execute ANYTHING as long as it ended with .BAT, .COM and .EXE. You can still "fool" Windows, with all of its fancy metadata to attempt executing random garbage if you use a FS without metadata (with fake .exe files the CreateProcess function may still offer a safeguard though. Dunno about .COM files).

Gez said:

Amiga OS didn't make use of file extensions. People used them as prefixes to sort their files by type.

Bollocks. You need .info's to go with a lot of executables in order to set them up prior to launching. Lose the .info and also make the program directly inaccessible from the GUI.

chungy said:

Most applications don't care, but Windows Explorer is particularly obtuse about it.

Get yo'self a better filemanager, yo!
http://vifm.sourceforge.net/

hex11 said:

vifm

Vifm is a ncurses based file manager with vi like keybindings. If you use vi, vifm gives you complete keyboard control over your files without having to learn a new set of commands.

vi

No.

Maes said:

No.

You do not understand the power of the vi side...
http://thomer.com/vi/vi.html

No, hex11, you are the keybindings.

What's funny is that I've used vi for years, but in the last few months I've been learning Emacs... and I like it a whole lot better. Does that make me a traitor? :P

chungy said:
Does that make me a traitor?

No, it just means you have ten fingers. On each hand.