Disk Utility looks for a .dmg extension now?

Posted:
in Genius Bar edited January 2014
I just got my new Intel Mac Mini and I'm copying stuff over. I then discover that an important disk image on a DVD backup won't mount. It mounted fine on the PPC. So, I copy the image onto my hard drive and see that the only thing wrong is it doesn't have a .dmg extension. It has the right icon and it opens in Disk Utility when I double-click it so I figure that surely it can't be dumb enough to want just a .dmg extension. But sure enough, after renaming it, it mounts fine.



Well, thank you Apple because now for every file that is burned to a DVD without a .dmg extension, I'm going to have to copy the files off and burn another disc.



Ok, it's perhaps my fault for not making sure the files are named right but there's no need to make my life more difficult for no reason whatsoever.



This happens with Quicktime too and it really annoys me. If you open some AVIs that are named .mpeg, Quicktime will throw up an error. Rename it to .avi and it's fine. The file hasn't changed so why prevent a file opening based on the name? Everybody else uses the file headers to open files and if the header checks out then what's the problem?



Is there a way to get hdiutil to skip that verify step or something so I don't have to burn any discs again?



edit: I tried it with some other DVDs that seem to be the same (no .dmg extension) and they mounted ok. I'm not sure why it would happen with one image and not any other.

Comments

  • Reply 1 of 2
    lundylundy Posts: 4,466member
    Blame this on Avie Tevanian.



    Everybody told him not to, but he wanted files to be "consistent" with Windows file extension crap, and there you have it.



    John objected to this too, and they didn't listen to him either.



    The absolute beauty of the file type and creator that made the Mac OS so easy to use and allowed you to name your file anything you wanted ... that's optional now.



    Universal Type Identifiers rule, but who the hell knows if there is a way to make them work on Windows.
  • Reply 2 of 2
    MarvinMarvin Posts: 15,326moderator
    Quote:
    Originally Posted by lundy


    Blame this on Avie Tevanian.



    Everybody told him not to, but he wanted files to be "consistent" with Windows file extension crap, and there you have it.



    John objected to this too, and they didn't listen to him either.



    The absolute beauty of the file type and creator that made the Mac OS so easy to use and allowed you to name your file anything you wanted ... that's optional now.



    Universal Type Identifiers rule, but who the hell knows if there is a way to make them work on Windows.



    I actually quite like the extensions idea as I find it easier to rename a file than open up a file type/creator editor but I think that it should be further down the hierarchy of how to recognise a file. The order should go:



    1. verify file header > pass > open file

    fail

    2. verify file type/creator info > pass > open file

    fail

    3. verify extension > pass > open file

    fail

    4. raise error



    It seems to be that some OS X programs (usually Apple ones) check the extension first.
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