Amiga questions you've always been too embarrassed to ask

[TuKo]

Originally Posted by Daedalus

Version >NIL: might not look useful, but it does actually do something - it opens version.library and also sets two environmental variables with the version information of Kickstart and Workbench. Other parts of the startup sequence can then check Kickstart or Workbench versions without having to run the Version command again.

Thanks ! That was the info I was looking for.

[daxb]

Originally Posted by Jope

Basically if you intend on using the If command's WARN/ERROR/FAIL parameters, 21 is the minimum FailAt level you can run at, so it is set in there for you.

http://wiki.amigaos.net/wiki/AmigaOS...d_Reference#IF

21 is only necessary if you want to use the FAIL keyword.The others should work without set a FailAt level. On my OS3.1 system it seems to be that the default value is 10 and S-S doesn't leaves FailAt to other/child CLI/Shell processes.

[Jope]

Originally Posted by daxb

S-S doesn't leaves FailAt to other/child CLI/Shell processes.

Yeh, I was thinking about it in more of a best practice kind of way, already there for you if you make modifications to the s-s. But I admit it was just a guess.

[Titler]

Originally Posted by MajicMushroom

What the hell is Bogo RAM?

From "Bog Standard" I presume...

[idrougge]

There is also "bogo MIPS" as a benchmark.

[Gorf]

Originally Posted by idrougge

There is also "bogo MIPS" as a benchmark.

and it is a bogus value

BogoMips are Linus's own invention. The linux kernel version 0.99.11 (dated 11 July 1993) needed a timing loop (the time is too short and/or needs to be too exact for a non-busy-loop method of waiting), which must be calibrated to the processor speed of the machine. Hence, the kernel measures at boot time how fast a certain kind of busy loop runs on a computer. "Bogo" comes from "bogus", i.e, something which is a fake. Hence, the BogoMips value gives some indication of the processor speed, but it is way too unscientific to be called anything but BogoMips.

http://www.clifton.nl/bogo-faq.html

[Gorf]

Originally Posted by MajicMushroom

What the hell is Bogo RAM?

AFAIK it is the same as certain slow RAM or "Ranger" RAM from C00000-D7FFFF

[malko]

Short version: Is DMS (DiskMaSher) able to handle non standard track and thus more information than ADF (Amiga Disk File) ? some kind of forerunner of the IPF format or is DMS == ADF ?

Long version: Back in the day, I remember a NDOS game (I forgot the name unfortunately) that was provided to me on two DMS file (something like tracks 1-40 on the 1st DMS file & tracks 41-79 on the 2nd DMS file).
It was straightforward to un-DMS those two files to a floppy disk and play the game.
Later I took this disk to a friend's house and as he had no free floppy disk we tried to DMS this game to a file on his HD. But we weren't able to do so.
We then took a quick look at the documentation of DMS but, as we were more interested in playing games than reading technical stuff, it was faster for me to return home and create a disk for my friend from the two originals DMS (I know shame on us... ) .

Since that time I had always the idea that DMS was better than other format like ADF (compression is not part of my question) but that only a few who managed to master this shell tool can use it to his full potential.

So is DMS (DiskMaSher) able to handle non standard track and thus more information than ADF (Amiga Disk File) or is DMS == ADF ?

[StingRay]

Originally Posted by malko

Short version: Is DMS (DiskMaSher) able to handle non standard track and thus more information than ADF (Amiga Disk File) ?

Short answer: no! DMS is for standard DOS disks only. Warpers were used for protected disks.

[malko]

Originally Posted by StingRay

Short answer: no! DMS is for standard DOS disks only. Warpers were used for protected disks.

Thanks for short answer

Will a long answer differ a little bit ? (meaning that a warper was maybe included in a late version of DMS ?)

[StingRay]

Originally Posted by malko

Will a long answer differ a little bit ?

No. DMS really is just for DOS disks, it doesn't handle any non-standard disk format.

[malko]

Originally Posted by StingRay

No. DMS really is just for DOS disks, it doesn't handle any non-standard disk format.

OK (so this game that we were not able to DMS again will remain a mystery until my death ).

One last question (if I am correct DMS is older than ADF) :
If DMS does the same job as ADF, do you know why the second has replaced the first one ? Is ADF better than DMS or is it just like that ?

[DamienD]

Originally Posted by malko

One last question (if I am correct DMS is older than ADF) :

Yes.

Originally Posted by malko

If DMS does the same job as ADF, do you know why the second has replaced the first one ? Is ADF better than DMS or is it just like that ?

DMS was first and used to compress normal DOS disks.

I might be wrong but as far as I'm aware, ADFs were created later when emulation came along... no need to compress anymore as file size / bandwidth were no longer an issue at this time.

DMS / ADF; both equal in terms of what type of formats they support i.e. standard DOS disks; but as StingRay already mentioned, don't handle any non-standard disk formats.

[TroyWilkins]

I could be wrong here (wouldn't be the first time, won't be the last), but I remember reading somewhere that DMS could also have problems with a particular data sequence that could be found, and thus would be unable to work on any disk that contained that particular data sequence.

If I'm wrong here, I'm sure someone will say so, and I welcome being corrected.

[Amiga1992]

I'm confused, ok yeah, DMS will not handle extended tracks or copy protection of any kind, but you can happily pack unprotected NDOS disks as afar as I remember. Am I remembering wrong?

[TroyWilkins]

Originally Posted by Akira

I'm confused, ok yeah, DMS will not handle extended tracks or copy protection of any kind, but you can happily pack unprotected NDOS disks as afar as I remember. Am I remembering wrong?

Sounds like an easy experiment for someone to conduct perhaps?

[Amiga1992]

Yeah I couldn't deal with this doubt! I went and DMSed a cracked game (Fire & Ice), and it worked just fine! I am glad my memory is not fading away.
Also I remembered that a lot of old Amiga warez collections had files in DMS format.

[TroyWilkins]

Yeah, I remember back when I was young, dumb and full of enthusiasm (and had little in the way of money) downloading DMS files from my local BBS, and I'm sure at least some of them didn't extract to disks that were explorable under Workbench.

[malko]

Originally Posted by DamienD

[...] ADFs were created later when emulation came along... no need to compress anymore as file size / bandwidth were no longer an issue at this time.
DMS / ADF; both equal in terms of what type of formats they support i.e. standard DOS disks [...]

Thanks Damien.
So let's say that the wheel was reinvented with ADF if there is no improvement over DMS .

Originally Posted by Akira

I'm confused, ok yeah, DMS will not handle extended tracks or copy protection of any kind, but you can happily pack unprotected NDOS disks as afar as I remember. Am I remembering wrong?

Here I am affirmative . Yes DMS is able to "pack" (reduce the size) so depending on the method used to pack, the resulting file would be smaller than the ADF one of the same disk.

Originally Posted by TroyWilkins

[...] but I remember reading somewhere that DMS could also have problems with a particular data sequence that could be found [...]

I might be wrong but as far as I know (I welcome being corrected also ), this is due to a "bug"/"misconception" in the routine that pack the tracks. So unpacked track (like ADF) are not concerned.

[StingRay]

Originally Posted by malko

One last question (if I am correct DMS is older than ADF) :

No!

Originally Posted by malko

So let's say that the wheel was reinvented with ADF if there is no improvement over DMS .

ADF is just a plain 1:1 image of an Amiga disk. It could be created back in the day already as long as you were able to read the disk into memory and save it to a file. Back then it wasn't called ADF of course but the "format" as such always existed. I for one for example often used ASM-One to read a disk completely into memory and save it. And I did that as early as 1991.

Besides, DMS has quite a few bugs so you can easily end up with archives containing wrong/broken data!