reparse points and "if exist file\" bug

Christoph Mueller

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Dec 12, 2006, 2:10:26 PM12/12/06

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hi
just a short info about some weird behaviour, since I have spend some
time traking down this bug and did not find anything about it online.
Apologies if this has been posted before.

To detect whether an object is a file or a directory/folder I used
if exist "%~1\" echo DIR
This should echo DIR only if the object is a directory

however, if the path to the file contains a reparse point/junction,
this test will always return DIR, even if the object is a file:

if exist "dir1\junction\dir2\file.txt\" echo DIR
will always echo DIR

This can be quite confusing if you do not not know that there is a
reparse point in the path.

What seems to work fine is the alternative method
dir /AD %1 | find "<DIR>" > nul
if not errorlevel 1 echo DIR
however this can be slow.

Are there any other such traps with reparse points?

Timo Salmi

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Dec 13, 2006, 9:10:46 PM12/13/06

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Christoph Mueller <> wrote:
> To detect whether an object is a file or a directory/folder I used
> if exist "%~1\" echo DIR
> This should echo DIR only if the object is a directory

As has been discussed fairly extensively quite some time ago, it is not
that simple
75} How do I detect if an object is a file or a folder?
179284 Oct 21 2006 ftp://garbo.uwasa.fi/pc/link/tscmd.zip
tscmd.zip Useful NT/2000/XP script tricks and tips, T.Salmi

All the best, Timo

--
Prof. Timo Salmi ftp & http://garbo.uwasa.fi/ archives 193.166.120.5
Department of Accounting and Business Finance ; University of Vaasa
mailto:t...@uwasa.fi <http://www.uwasa.fi/~ts/> ; FIN-65101, Finland
Timo's FAQ materials at http://www.uwasa.fi/~ts/http/tsfaq.html

Christoph Mueller

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Dec 13, 2006, 11:00:07 PM12/13/06

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Timo Salmi wrote:
> As has been discussed fairly extensively quite some time ago, it is not
> that simple
> 75} How do I detect if an object is a file or a folder?
> 179284 Oct 21 2006 ftp://garbo.uwasa.fi/pc/link/tscmd.zip
> tscmd.zip Useful NT/2000/XP script tricks and tips, T.Salmi

I am well aware of that resource, it is quite useful, thanks
In fact this is where I got the way I am currently using to detect
directories, namely
dir %1 | find "<DIR>" > nul
if errorlevel 1 ...

I modified the first line to
2>nul dir /AD %1 | find "<DIR>" > nul
in hopes of speeding it up a bit for directories with lots of entries.

But the tips also still contain the solution
if exist "%~1\" (...
which apparently works fairly well as long as the path does not contain
any reparse points, but fails silently if it does.
I found no mention of that in previous discussions about the topic.

So I would suggest adding a warning to that tip.

Timo Salmi

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Dec 14, 2006, 1:28:57 AM12/14/06

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Christoph Mueller <net...@gmx.net> wrote:
> Timo Salmi wrote:
>> As has been discussed fairly extensively quite some time ago, it is not
>> that simple
>> 75} How do I detect if an object is a file or a folder?

> But the tips also still contain the solution

> if exist "%~1\" (...
> which apparently works fairly well as long as the path does not contain
> any reparse points, but fails silently if it does.
> I found no mention of that in previous discussions about the topic.
>
> So I would suggest adding a warning to that tip.

Thanks Christoph. I'll add a Message-Id pointer to your contribution.

All the best, Timo

--
Prof. Timo Salmi ftp & http://garbo.uwasa.fi/ archives 193.166.120.5
Department of Accounting and Business Finance ; University of Vaasa
mailto:t...@uwasa.fi <http://www.uwasa.fi/~ts/> ; FIN-65101, Finland

Useful script files and tricks ftp://garbo.uwasa.fi/pc/link/tscmd.zip