Bug in DIR command? | Tech Off

mawcc
Make it so

Today I've been researching an error where an ASP.NET image handler would display a wrong screenshot. Interestingly it turned out that the Directory.GetFiles method as well as the DIR command list a wrong file in wildcard mode:

As can be seen, the first file shouldn't belong in this list. The directory contains close to 5000 files, and when I copy the 4 files from above into an emtpy directory the error doesn't appear.

blowdart
Peek-a-boo

It's the 8.3 file name; try dir /X then compare the results with your wildcard

mawcc
Make it so

In reply to blowdart

#Jul 1st, 2008 @ 3:04 AM

Your're right, thanks. Is there a way to force Directory.GetFiles to consider only long file names? I couldn't find anything in the docs.

Btw, a "gci 13440*" in Powershell does the correct thing.

Dexter

In reply to mawcc

#Jul 1st, 2008 @ 3:43 AM

No, you cannot make GetFiles return only long filenames but you can post filter them yourself. An

if (fileName.StartsWith("13440", StringComparison.OrdinalIgnoreCase))
{
...
}

will do the right thing. I wouldn't be too surprised if PowerShell does exactly the same thing.

PerfectPhase
"This is not war, this is pest control!" - Dalek to Cyberman

In reply to mawcc

#Jul 1st, 2008 @ 3:43 AM

Guess you could turn 8.3 off http://support.microsoft.com/kb/121007

littleguru
<3 Seattle

We still need to deal with this kind of things... wow this is crazy.

jh71283
Throw new System.Beverage. OutOfCoffeeException()

In reply to littleguru

#Jul 1st, 2008 @ 2:24 PM

I might be daft, but I don't see why this should be a problem for 8.3.

13434_13434 should surely be abbreviated to 13434_~1.xxx in 8.3?

Then it would not match the wildcard that mawcc has pointed out.

Dexter

In reply to jh71283

#Jul 1st, 2008 @ 11:52 PM

Not always. It really depends on how many files you have in that directory and how "similar" they are. Here's an example:

00CD04~7.TXT 00000000-10002787.txt
00C114~5.TXT 00000000-10002788.txt
00C514~3.TXT 00000000-10002789.txt
00C1F5~4.TXT 00000000-10002790.txt
00C5F5~4.TXT 00000000-10002791.txt

As you can see the short names are quite different and they'll match a dir wildcard like 00C*