I obviously must have had the files on the same volume when I tested this previously. I just tried again and it doesn't work. I wish I could recall what I did the first time.
If you find a solution that works, please post it here. About a month ago I was working on converting a bunch of linux scripts over to Windows, and I got stuck at some scripts that were linking files from another volume (actually an NFS volume on another machine altogether). I never found a Windows equilivant command for this.
blindwig, you can do more than assume that directories are using anything, I mentioned in my original post that directory linking uses an NTFS junction point.
OK, when I did directory linking, I was using the MOUNTVOL and DISKPART commands under Windows XP. According to this page (MS Q205524)
the MOUNTVOL command does use NTFS junction points, so yes that's what I was using before.
But again I warn you that they are very flaky. Here's an easy way to crash Window Explorer every time:
Create 2 volumes
Mount a folder from volume 2 into a folder on volume 1
start exploring volume 1 and navigate until you are looking at the folder that is linked to volume 2
delete a file out of this folder
exlporer will try to move the file that is on volume 2 to the recycle bin on volume 1. It will fail. It will hang for a while as it keeps retrying the failed operation, until eventually it just crashes.
It's quirky stuff like that that makes me warn people not to use junction points until MS gets all the bugs worked out.