The accuracy of ISO images for an old DOS CD-ROM

[Chris123]

Hi,

 

Many years ago I made a compilation of DOS games and burned it on a CD-ROM which was designed to work on an actual DOS machine. The only Windows-y thing about the CD was long directory names. For some reason, this caused a problem, and the long-named directories were inaccessible under DOS. I eventually found out that the problem was that I built the directories of the compilation under WinXP. So, I rebuilt the compilation under Win98, changed some Nero settings to make the CD more DOS compatible, burned another copy, and this time it worked fine.

Note that MD5-wise, the data was identical on both discs.

 

Luckily, the disc hasn't deteriorated yet, so I wanted to make an image out of it for safe keeping, until I build a DOS machine again.

My question is this - I used ImgBurn to create the image, and I was surprised to find that the image format that ImgBurn chose for this CD is ISO rather than BIN/CUE. The data was preserved perfectly, of course, but that's irrelevant to whether this image will properly work on a DOS machine once reburned onto a disc - is an ISO image accurate enough for preserving whatever enabled this disc to work on a DOS machine back in the day? Wouldn't a binary image be the correct choice?

 

Thanks

 

 

P.S.

Off-topic - will ImgBurn notify if file\folder names are getting truncated during burning? And what about file\folder name change due to unicode characters?

[Rincewind]

Wouldn't a binary image be the correct choice?

 

ISOs are technically binary data. As far as a BIN/CUE format, in this case you can't have that format because your original disc is most likely a single session disc burned as MODE1/2048 instead of MODE2/2352. BIN/CUE is only reserved for MODE2 or multi-session discs.

 

As far as any sort of truncations with filenames this really depends on how you set the restrictions. You can actually be relatively lax. Just look in the settings when burning a disc, click on the advanced tab, restrictions tab, and look at the iso9660 tab.

[LIGHTNING UK!]

BIN/CUE and ISO have nothing to do with file name lengths. The one the program uses by default all depends on the way the disc was written (Mode 1 or Mode 2).

 

Yes, the program will tell you about file/folder name truncation etc in the Log window - keep it open at all times.

[Chris123]

Thanks for replying.

 

BIN/CUE is only reserved for MODE2 or multi-session discs.

Odd, I'm sure I created BIN\CUE images out of MODE1 CDs. I think I was using CDRWIN.

 

BIN/CUE and ISO have nothing to do with file name lengths. The one the program uses by default all depends on the way the disc was written (Mode 1 or Mode 2).

Yes, I know that the image formats are not related to file name lengths, that was an off-topic question. My main concern is whether the ISO image is accurate enough to preserve whatever made the CD work properly on DOS, and if it will transfer to a CD when I reburn the image.

[LIGHTNING UK!]

You probably did but it's pointless.

 

Why make something less compatible when there's no benefit in doing so?

 

ImgBurn uses BIN/CUE when it needs to and ISO when it doesn't.

 

For a Mode 1 disc, ISO is 100% as accurate as BIN/CUE.

 

You're over-thinking things.

[Chris123]

You probably did but it's pointless.

 

Why make something less compatible when there's no benefit in doing so?

Didn't know this fact until right now. Thanks for the info.

 

For a Mode 1 disc, ISO is 100% as accurate as BIN/CUE.

That's what I needed to know. So I guess if the ISO image that ImgBurn created didn't completely preserve the layout of my disc, nothing will. I still don't know what property Win98 'attached' to the long-named folders that made them accessible under DOS, but I hope it's something that can be transferred to an image.

 

You're over-thinking things.

Yep, that's me. Too old to change that. It has its benefits though.