Monday, February 04, 2008

User group one: Winzip ignores NTFS attributes stored in alternate data stream

Occasionally I come across an issue nobody but me cares about.

Ok, more than occasionally.

These are "user group one" issues -- as in a user group with one member. (Thank you Andrew.)

I, for example, am the only person in the known universe who uses NTFS file attributes. I tweak my Explorer views to show the comment field in list view, for example. I even show the Title field! [1]

Being the only person who does this, I'm the only person to discover that WinZip 10 doesn't store these attributes. I'm guessing XP stores them in the NTFS alternate data stream [2] and WinZip ignores the ADS attributes [3]. I found this out when I unzipped some work and lost my metadata.

This is all very annoying.

To the user group of one.

[1] Not only does this introduce functionality that came with PC Magazine's DOS based application in 1985, it also allows me to provide documentation on file shares about what certain data sets are good for. In addition Sharepoint honors these attributes (which Office apps reflect back into their internal attribute store), so I don't have to re-enter them when I upload files to my Sharepoint Libraries.

[2] Windows NT server had a very robust Macintosh file share service, it stored MacOS Classic resource forks in the NTFS alternate data stream. Later, some aftermarket solutions (DAVE) did the same thing. Worked great.

[3] I have a vague recollection that XP's copy command may ignore them too, and many backup products miss 'em.

1 comment: said...

1) EAs are indeed in ADSs.

2) 'XCopy' does copy them. (Very annoying when one tries to use it to remove ADSs from an entire directory full of files.)