OS X Tiger format

Discussion in 'macOS' started by mcs37, May 26, 2005.

  1. mcs37 macrumors regular

    mcs37

    Joined:
    Mar 2, 2003
    Location:
    Washington, DC
    #1
    I don't have Tiger yet, but I am curious -- is it formatted with the UDF file system or the old ISO9660 (probably level 2 with other extensions)?

    Thanks,
    mcs37
     
  2. iindigo macrumors 6502a

    iindigo

    Joined:
    Jul 22, 2002
    Location:
    San Francisco, CA
    #2
    Could you be more specific - Do you mean hard disk formats or CD formats, or ...?

    If you're talking about the hard disk formatting, it's just good ol HFS+, like Macs have used since like Mac OS 8 in 1997 -

    EDIT: if you're talking about the installer DVD's format, it's HFS+ as well -
     
  3. mcs37 thread starter macrumors regular

    mcs37

    Joined:
    Mar 2, 2003
    Location:
    Washington, DC
    #3
    My bad -- yes, I meant the format of the DVD itself. Is HFS+ a Mac-specific standard (perhaps extension to UDF?)
     
  4. iindigo macrumors 6502a

    iindigo

    Joined:
    Jul 22, 2002
    Location:
    San Francisco, CA
    #4
    Yes, HFS+ is a Mac-specific standard. It stands for Hierarchal File System Plus, and is not an extension on UDF but rather an extension on the original HFS. HFS is not based on anything - Apple created it for the Mac to use back around 1990 or so.

    If you're curious, the original Mac's filesystem was MFS, which stood for, you guessed it, the Macintosh File System. It wasn't all that great - it didn't support nested directories, or special characters in filenames, and a few other things. This is why Apple created HFS. Later on, in about 1997 when Apple created Mac OS 8, they updated HFS to HFS+. I'm not exactly sure of the benefits of using HFS+ of regular HFS except that HFS+ was more efficient with drive space.
     
  5. Makosuke macrumors 603

    Joined:
    Aug 15, 2001
    Location:
    The Cool Part of CA, USA
    #5
    HFS+ is a drastic improvement over HFS for more than just block size. It:

    -Increased the maximum number of allocation blocks from about 65,000 to around 4.3 billion. This both reduced the size of the smallest file that can be stored and increased the number of individual files that can be stored.
    -Increased the max volume size from 2TB to a theoretical limit into the Exabytes (though I think as of 10.3 the largest OS supported volume was 16TB).
    -Increased maximum individual file size from 2GB to 2TB (and even that might be just an OS limit--not sure).
    -Increased maximum number of characters in a file name from 31 to 256.
    -Converted the entire filesystem from roman script to full Unicode, allowing non-English languages to store files on equal terms (this was actually a biggie).


    On a side note, it's funny to think about the block size issue; 65K blocks was plenty when hard drives were only 20MB and the OS only consisted of a few hundred files--one of those spacious 20MB disks could easily be broken down intoh 512 byte blocks, and nobody had owned a hard drive long enough to create 65,000 files.

    Eventually, that didn't cut it--I remember having 64K blocks on a disk and being so relieved to regain several dozen megabytes of space by converting to HFS+. In fact, you couldn't even install OSX on a disk limited to 65,000 files and were you able to format a modern 400GB disk that way the smallest file you could store would be 6MB. Ouch.

    The whole unicode thing is huge too, though.
     

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