LLVM Wallpaper and OS X's xattr

For the past few months I've been using this as my wallpaper/desktop background. I'm seldom a fan of any personality or any project, but hey it's LLVM.

I finally found out the source of the picture. It's made by putting the LLVM logo over one of Cocoia's wallpapers.

How did I find out the source? I must have seen the link from some friend's twitter long time ago, but the friend's tweets are locked, and Twitter's search is not really helpful.

So how did I finally find out? Surprisingly, via Get Info in Finder! Essentially, it's the xattr (extended attributes) in the file. Since 10.5, all files downloaded by Safari carry an xattr called You can use the command line tool xattr to inspect those attributes. The attribute values are in the form of property lists.

I find this a good point to show the importance of file system advance and why metadata matters.