What's in an MP3's resource fork..? [Was: Re: [X4U] ._annoying_files on SMB shares - can I remove them..?]

[Stroller]

On Apr 10, 2004, at 3:12 pm, Alex wrote:
>>
>>> ._FileName are separate files where the content of the resource fork 
>>> is stored. Mac files have two forks, a data fork and a resource 
>>> fork. This file architecture is incomprehensible to other OSs, so 
>>> the most common effect of copying a Mac file to a foreign OS is the 
>>> stripping of the resource fork. To avoid this, when copying to a Win 
>>> volume, Mac OS X copies the content of the resource fork to a 
>>> separate file.
>>
>> [...] Okies, so what applications NEED the data in the resource 
>> fork..?
>
> There's no hard-and-fast rule. For instance, I believe you mentioned 
> InDesign. This one stores the PICT preview in the resource fork, so 
> you should still be able to open .indd files on Windows or Mac even if 
> the resource fork is stripped.
>
> By and large, you may assume files from x-platform apps (e.g., 
> InDesign, Illustrator, FileMaker, Office, etc.) either won't have a 
> resource fork or won't have any critical data there; while Mac-only 
> apps may store important data in the resource fork.

Sorry to be bringing this up again, but I'm now in the middle of 
writing my killer Bash script for removing unwanted .DS_Store from SMB 
shares.

      echo "Looking for .DS_Store files left by Apple's Finder in $path" 
 >&2
      FILES=`find $path -name .*DS_Store`;
      for file in $FILES
      do
        if [ `file -b $file` = "data" ]
        then
           rm $file
        fi
      done

Since I figure it's possible that a user might name an important 
document .DS_Store, I use `file` to check that they're the same 
filetype as all the other .DS_Store I had lying around to check 
against. I don't think there's any other way to determine 
programatically whether ._DS_Store files are really the anticipated 
Finder-droppings rather than lurking Word documents, although I've been 
interested to note that all of mine from this evening's session are 
either 6148 bytes long, or double that, 12292.

So I think it's safe to say that the resource forks of jpegs and other 
images can safely be removed, as with Word .doc files. But what about 
those of MP3s..? Does iTunes keep any data there..? What about any 
other filetypes of which the resource forks are either essential or 
unimportant..?

Thanks,

Stroller.