[Zoom]

Okay... so I'm trying to put a bunch of songs from my iTunes library onto an external hard drive - not my entire library, but a significant subset - about 4500 songs.

I plugged in an external USB hard drive (in this case a WD MyBook). I first tried creating a playlist in iTunes of all the songs I wanted, selecting all the tracks, and dragging them to the open Finder window on the external drive. That didn't work at all. Okay, so I figured iTunes disallows that. Fine.

So I opened the actual iTunes library folders in Finder. I option-selected a bunch of artist folders - a b few dozen from the "A's". I figured I'd do it in chunks in case I fat-fingered a select and lost everything. I dragged them over and dropped them on the external drive. Only the first three folders copied over. I deselected those first three folders using option-click, and tried again. Only the next three folders were copied. ?!?

I thought that maybe something weird was going on with that drive. It's formatted for Windows and used as a Windows Backup drive, too... so who knows, maybe there's some weird formatting problem.

So I plugged in a 4GB USB thumb drive to my Mac. I tried to copy the few dozens artist folders again via drag and drop. This time the OS showed me an explicit circle with a slash through it - NO, you can't do that! Hmm... I tried selecting just three folders... same thing. But when I selected only two artist folders, then I got the happy green "+" icon and I could copy!

Now I'm thinking - okay, this is an Apple conspiracy - they're blocking the mass-copying of files from the iTunes library to external drives! But just to be sure, I tried another set of folders, from my personal Documents. Same thing. In fact, I noticed that you see the circle with a slash as soon as you start to drag the folders (ie, when your mouse focus is still in the source folder). And the same happens for files, too - 1-2 is fine, 3 or more will fail.

What's going on here?

I've got 10.6.6.

[Zoom]

Hmm.... well, a restart seems to have fixed this problem. I wonder if the iTunes copy attempt somehow horked things up in Finder.

I tried this on a laptop, too, that was 10.6.6 - it had no trouble selecting multiple files and dragging them around.

Something in the OS got messed up, and I'm not sure how - but restarting seems to have cleared it up.

[P]

Has the external drive been reformatted to HFS+? If it's still on FAT32, that might cause it.

[Zoom]

Well, it's definitely Windows formatted - not sure if it's specifically FAT32. It was formatted using Windows 7, I believe.

Why would this cause this problem? As I said, I saw the problem with a thumb drive, too. And the circle with the slash was visible before I ever dragged the files from the source window (ie, it didn't know where I was going to drop them yet).

I think iTunes caused the Finder to get in a weird state. I was dragging 4500+ files around - which by the way took my Mac forever to resolve - and I think it somehow horked up the Finder. That is, I would select all in the playlist, which was immediate, and then I'd try to drag them to a Finder folder - and it would have to think about that for like 10-15 second before my mouse cursor would have the little red thing showing the number of files I was dragging. And when I dropped them, it would take a little while for it to show me the "fly back" thing when the drop failed.

[Spheric Harlot]

If it's NTFS, it's not actually supported (or rather, read-only), so it's kind of a surprise that it would do any writing at all.

If it's FAT32, there's all sorts of restrictions on filenames - a bunch of characters cannot be used, maximum filename length, maximum pathname length, etc.

Trying to copy directories that violate those restrictions (say "iTunes/iTunes Media/Music/Eugene Ormandy and the Philadelphia Philharmonic Orchestra/Rachmaninov - 2nd Piano Concerto"), it will start to do its thing and then conk out.

[P]

Originally Posted by Spheric Harlot 

If it's NTFS, it's not actually supported (or rather, read-only), so it's kind of a surprise that it would do any writing at all.

If it's FAT32, there's all sorts of restrictions on filenames - a bunch of characters cannot be used, maximum filename length, maximum pathname length, etc.

Trying to copy directories that violate those restrictions (say "iTunes/iTunes Media/Music/Eugene Ormandy and the Philadelphia Philharmonic Orchestra/Rachmaninov - 2nd Piano Concerto"), it will start to do its thing and then conk out.

Yes, that last what I was referring to. To be fair, Windows doesn't handle it much better. It will even fail with long pathnames and NTFS under certain circumstances.

FAT32 is also picky about characters in the filename. I've seen copies fail for that reason as well.

[Zoom]

So, after a restart, I was able to drag and drop an arbitrary number of folders from my iTunes library to the external hard drive. It didn't complain at all, and I'm sure there were some weird/long names in there, like Motley Crue (with umlauts).

I didn't even attempt to drag and drop from iTunes app/playlist.

Can you export playlists and import them to another instance of iTunes? I'm guessing not since iTunes explicitly doesn't support this sort of thing.

[P]

Originally Posted by Zoom 

Can you export playlists and import them to another instance of iTunes? I'm guessing not since iTunes explicitly doesn't support this sort of thing.

Yes. Under File -> Library-> Export playlist (or just rightclick on one in the sidebar), and then select M3U. To import, just drop it on the sidebar of the new iTunes installation.

[Zoom]

Okay, I'll give that a shot. I read about that somewhere... I think you have to hand-edit the resulting XML to point to the new hard drive location, right?

Also, ratings will be lost on the songs, at least the way I copied them. And some of my playlists are smart playlists that use that info.

[P]

Originally Posted by Zoom 

Okay, I'll give that a shot. I read about that somewhere... I think you have to hand-edit the resulting XML to point to the new hard drive location, right?

Also, ratings will be lost on the songs, at least the way I copied them. And some of my playlists are smart playlists that use that info.

M3U playlists are portable, I think - I copied many of mine from a Windows installation looooooong ago, and it all worked. The XML format I don't know.

[Zoom]

There may be some way to export relative playlists, but when I just did it, the contents were absolute - which didn't work when I imported them. Again, I'm going from Mac to PC - if you were going Mac to Mac or PC to PC, it would probably be fine, if both machines used the default music location and the user IDs were the same.

Here's a simple Perl script I wrote to fix my playlists.

Code:
# Fixes iTunes playlists from a Mac so they'll work on a PC.
# Basically just changes the root location of the files.
# This file processes all .m3u files in the current directory and
# saves the updated/fixed versions in a directory called "fixed".

$outdir = "fixed";

# Okay if directory already exists.
mkdir($outdir) || print "Failed to create directory $outdir: $!\n\n";

# Get the list of all files in this directory
@lists = <*.m3u>;

$count=@lists;

print "Found $count playlists.\n\n";

foreach $list (@lists) 
{
	print "Processing playlist $list...\n";

	open (INLIST,"<$list") || die "Can't open input playlist $list: $!";
	open (OUTLIST,">$outdir/$list") || die "Can't open output playlist $outdir/$list: $!";

	while (<INLIST>)
	{
		# Change Mac line endings to Windows.  Not needed, but easier to view the output.
		$_ =~ s/\r\n?/\n/g;
		# Change the path separators from / to \
		$_ =~ s/\//\\/g;
		# Change the Mac path to the Windows path
		$_ =~ s/\\Users\\MacUserID\\Music\\iTunes\\iTunes Music/C:\\Users\\WinUserID\\Music\\iTunes\\iTunes Media\\Music/g;
		print OUTLIST $_; 
	}
	close (INLIST);
	close (OUTLIST);
}

You'll need to replace "MacUserID" with your Mac user ID, and "WinUserID" with your Windows user ID.

Name this file something like "fix-playlists.pl" and run from a DOS prompt. As I say in the comments of the script, you'll want to run this in the directory with your .m3u files. The output will go in a directory called "fixed" with the same names. Then just import these from iTunes on the PC.

You could easily modify this to go the other direction, too. And I'm sure there are slicker ways to do this in Perl, but this works.

If you don't have Perl installed, you can get it for free from ActivePerl.

[Zoom]

Weird... when you import the songs, the track names appears as "track name - artist name". But as soon as you play the song, it gets corrected to just the track name.