"Houston, we have a problem"

This week was the 50th anniversary of humanity (ok the russians) breaking into orbit with Sputnik, giving the entire american nation the chills in the prospect of losing the space game. But intense competition encourages haste and in the end USA had the last laugh sending Louis Armstrong to check whether the moon was made of cheese. Or did they? Bad tongues and conspiracy theorists (not all of them greeks) claim that the whole thing was a scam, e.g. how come that US flag on the moon is flat? There's a perfectly good explanation for this, the whole thing must have been filmed in southpark where local weather conditions cause this peculiar cardboard flag syndrome :)

A bit closer to ground control, we can still find weird and unexplainable things. Take reparse points for example. This is a NTFS 5 feature which means they were available since windows 2000 but it has received little attention and even less use. I consider myself partly responsible; despite many user's requests I was dismissing folder junction support in xplorer² since I couldn't see the point. But useful they are nevertheless. So what are they?

Folder junctions are like shortcuts to folders. They are small control nodes in the filesystem redirecting to a different part of the filesystem. Unlike folder shortcuts (i.e. LNK files), junction points are completely transparent, they appear as normal folders. But when you enter a folder junction you jump to the actual folder hierarchy it represents, through a back door. With this mechanism you effectively reorganize your folder structure without breaking applications that cannot work with folder shortcuts directly. For example in Vista they are used for redirecting legacy folders. Of course we wouldn't need redirection if m$ didn't unecessarily rename basic folders like c:\documents and settings in the first place, but that's another story.

You can manipulate reparse points using xplorer². To create one, first you <ctrl+C> copy the folder that is the intended target, let's say d:\extra\data. Then switch to the folder that will hold the junction c:\organize and use Edit | Paste special | Folder junction | Paste giving it a name, e.g. moreData. From now on, entering c:\organize\moreData will show the contents of d:\extra\data. Note that unlike hard links, junctions can point to different volume names (C to D in this example). Sadly network targets are not supported, except through mapped drive names.

A word of warning: junctions appear so identical to real folders even on the filesystem level, so when you delete a junction point you risk removing all the files and folders it points to, without warning! If you want to remove just the junction you've created, select it and use Edit | Paste special | Folder junction | Delete. The only hint you get for junctions is a J attribute, if you have the attribute column shown that is. If you use folder junctions I recommend giving them names that shout "careful, I'm a junction", and also give them different color using a rule that detects the J attribute (Customize | Color coding menu command). When they stand out like that you are less likely to foobar your files by accident.

I conclude with a short demo on junctions. Being not the most organized person in the world, I ended up having data files in three different locations, scattered on my hard disks. To back them up every week I had to do three robust copies to my external hard disk. Using junctions I created a fake folder that gathers all the data folders under one roof, so from now on I can backup in one go. What a happy camper!

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