Fun with wildcards and DOS 8.3 filenames
I’ve found under some circumstances, new versions of Windows (XP and 2000, using NTFS) are still looking at the DOS 8.3 versions of filenames when using wildcards.
Real world example: a set of files such as tpo12345.xml tpo12346.xml tpo12347.xml etc. To find these, you’d use a wildcard such as tpo?????.xml
If you have a file called tpo1234567890.xml, it shouldn’t match using this wildcard, but it does, because the filename’s backward-compatible short version (in DOS 8.3 format) is something like TPO123~1.XML, which matches. It appears to only happen when the first part of the wildcard (without the suffix) is 8 characters long.
So it may be ten years since most of us said goodbye to short filenames, but it seems they’re still with us. I wonder if Windows Vista will still use them?
- Some details on how long filenames work
- The same behaviour manifests itself in VB Classic’s dir function. I haven’t checked for it in the VBScript File System Object.
June 1st, 2006 at 23:28
The famous Raymond Chen expands on this issue in his blog at http://blogs.msdn.com/oldnewthing/archive/2005/07/20/440918.aspx.
Note to disable the 8.3 name creation on XP NTFS partitions, use the command “fsutil.exe behavior set disable8dot3 1″
http://support.microsoft.com/kb/121007/