Short File Names

The CBFS class includes optional support for short filenames (also known as "8.3" filenames), which allows files to be accessed using the 8.3 name format: an 8-character name followed by a 3-character extension, separated by a period, containing no spaces. A CBFS-based virtual filesystem may need to enable this feature, e.g., in order for its files to be accessible to some older, third-party software which only knows of the 8.3 name format.

In CBFS, the UseShortFileNames property is used to indicate whether a virtual filesystem supports short filenames; it is disabled by default. Virtual filesystems that do advertise short filename support must also:

• Be able to generate short filenames that uniquely identify any and all files.
• Be able to map between files' normal (i.e., "long") and short names, in both directions.
• Be sure to return files' short names when handling the EnumerateDirectory and GetFileInfo events.
• Be able to handle a short filename being provided (instead of a normal one) in any event.

For more information about short filenames, please refer to this section of Microsoft's file naming article.