Tuesday, 15 April 2014

All I want to do is extract files from an ISO!

During testing of MakePartImage, I found that 7Zip did not extract a few of them correctly.
I had an ISO which I made of my Win7 Install DVD using MagicISO.
If I viewed or extracted the contents  in 7Zip or PeaZip, I get




The ReadMe.txt says that the file is in UDF format,
This disc contains a "UDF" file system and requires an operating system
that supports the ISO-13346 "UDF" file system specification.

Both WinRAR and Windows 8.1 Explorer can view the correct contents, so why can't 7Zip and PeaZip?

So, I changed MakePartImage to use WinRAR. Then I discovered two things:

1. WinRAR had faults extracting some linux ISOs, it converted all the filenames into uppercase and also converted hyphens and multiple dots in filenames ( - and .) incorrectly into underscores! e.g. extracting from antergos-2013.11.17-i686.iso. WinZip also did the same thing on this ISO. Windows Explorer also shows all uppercase names.

2. WinRaR is not freeware, so I can't add it to my download and distribute it!

I tried a few other free unzip utilities that supported a command line, but they also had similar problems.

Who would of thought it is so hard to unzip an ISO reliably in this day and age?

So now I have gone back to using 7Zip, but if it detects a UDF-only ISO that 7Zip cannot handle, I ask the user to download and install WinRAR, so that I can automatically use that to extract the ISO when 7Zip fails.


P.S. ISO Workshop seems to work correctly with all the ISOs, if you need a good ISO extractor - www.glorylogic.com