short file names

NTFSD
1

I do not have space anywhere in my filesystem to store short file names.
How can I properly handle short file names in my Windows XP FSD?

Thanks,
Jeremy

2

Three options:

  1. Make space (just to be complete - I assume this isn’t an option)
  2. Don’t support them. Note that NTFS has a registry switch to disable
    generation of short names. You will have to take the hit to determine
    the compatibility impact of this on the customers of your FSD - we only
    offer the switch in NTFS to allow people to run in that mode when they
    assert their system won’t have shortname dependencies.
  3. Synthesize them on the fly through a hashing mechanism. For example,
    note the method used by UDF (http://www.osta.org), which is the one used
    in Windows UDFS and similar to the one we use in CDFS. Note there is no
    attempt to detect hashing conflicts where

foobarbazqux.txt -> foob#4E8.txt
foobarbazquux.txt -> foob#4E8.txt

might occur. I believe you can just lift the UDF algorithm if you want
it, though of course IANAL and you probably have some nearby.

Dan Lovinger
Microsoft Corporation

This posting is provided “AS IS” with no warranties and confers no
rights.

-----Original Message-----
From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of Jeremy Sherrill
Sent: Thursday, February 19, 2004 2:19 PM
To: Windows File Systems Devs Interest List
Subject: [ntfsd] short file names

I do not have space anywhere in my filesystem to store short file names.
How can I properly handle short file names in my Windows XP FSD?

Thanks,
Jeremy

Questions? First check the IFS FAQ at
https://www.osronline.com/article.cfm?id=17

You are currently subscribed to ntfsd as: xxxxx@windows.microsoft.com
To unsubscribe send a blank email to xxxxx@lists.osr.com

3

> 3) Synthesize them on the fly through a hashing mechanism. For example,

The source code for any open source UNIX-based DOS VM (“dosemu”, “dosbox”)
etc - can also be the source of the algorithm.

Maxim Shatskih, Windows DDK MVP
StorageCraft Corporation
xxxxx@storagecraft.com
http://www.storagecraft.com

4

The only thing I’d note is that you want as much information in the hash
as you can. For instance, you want more than three hexadecimal
characters (0-9A-F). 0-9A-Z would be better; UDF’s base41 is about as
good as I could come up with at the time. The more bits of your hash
that you can represent, the fewer collisions you can expect.

Dan Lovinger
Microsoft Corporation

This posting is provided “AS IS” with no warranties and confers no
rights.

-----Original Message-----
From: xxxxx@lists.osr.com
[mailto:xxxxx@lists.osr.com] On Behalf Of Maxim S. Shatskih
Sent: Friday, February 20, 2004 10:28 AM
To: Windows File Systems Devs Interest List
Subject: Re: [ntfsd] short file names

  1. Synthesize them on the fly through a hashing mechanism. For
    example,

The source code for any open source UNIX-based DOS VM (“dosemu”,
“dosbox”)
etc - can also be the source of the algorithm.

Maxim Shatskih, Windows DDK MVP
StorageCraft Corporation
xxxxx@storagecraft.com
http://www.storagecraft.com

Questions? First check the IFS FAQ at
https://www.osronline.com/article.cfm?id=17

You are currently subscribed to ntfsd as: xxxxx@windows.microsoft.com
To unsubscribe send a blank email to xxxxx@lists.osr.com