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Cyberdude
01-22-2010, 05:16 PM
I’ve been trying to make sense of the Windows 7 file system and at the moment I’ve been “exploring” the Windows Explorer display. And here’s my questions about “WinEx”:
In my “Computer” library there are three folder entries:

$Recycle Bin
....Recycle Bin
....Recycle Bin

The properties in each of these entries call these items “folders”. And indeed the bottom two appear to be folders within the first (top) folder.
Q1: What is the significance of the question mark in the top folder?
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The bottom 2 folders each contain the names of about 25 files (as expected), but the bottom folder’s list is identical to the folder above it.
Q2: What is the purpose of having two folders with the same name and contents?
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In another part of the WinEx list being displayed is an entry named “Templates”. When I click on that entry, I get the following error message:

“C:\Users\Sid\Templates” is not accessible.
Access is denied.


In the title bar of the message is this:

“Location is not available


Q3: What does that mean?? I see this kind of entry a LOT. If it’s not accessible, then why bother to display it?? When i see the word accessible, security comes to mind. Since I have the highest security rating (I’m the only one using this computer at home), it seems unlikely that security is the problem.
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This brings up another question regarding deleting an entry displayed in WinEx.
Q4: Hypothetically, if I see two identical folder names at the same level (one is not a child of the other), is it OK to delete one of the two? It seems to me that I read in Help somewhere that deleting a folder deletes from the computer everything that is a child of that folder. In the case above (duplicates), then would all files in the deleted duplicate folder be also deleted from its duplicate too? That’s a scary problem.
Sid

Paul_Hossler
01-22-2010, 06:20 PM
Vista, and I assume Win7, implimented Junctions, Symbolic Links, and a whole lot of other file stuff that I don't understand.

Maybe (bold, underlined) this link would help explain why the same folder shows up several places.

http://www.jimmah.com/vista/Security/junctions.aspx


This link has a great tool that allows you to make your own easily, but I also like their explaination of the whole concept (even if I don't understand it)

http://schinagl.priv.at/nt/hardlinkshellext/hardlinkshellext.html



Hardlinks are a feature common to many Unix based systems, but are not directly available with NT4/W2K/WXP. It is a feature, which must be supported by the file system of the operating system.
So what are Hardlinks? It is common to think of a file as being an association between a file name and a data object. Using Windows Explorer, the file system can be readily browsed, showing a 1:1 relationship between the file name and the data object, but this 1:1 relationship does not hold for all file systems.
Some file systems, including UFS, XFS, and NTFS have a N:1 relationship between file name and the data object, hence there can be more than one directory entry for a file.
So, how does one create multiple entries for the same data object? In Unix there is a command line utility ln, which is used to create link entries for existing files, hence there are many file names, or so called Hardlinks, for the one data object.
For each HardLink created, the file system increments a reference count stored with the data object, i.e. it stores how many file names refer to the data object, this counter is maintained (by the file system) within the data object itself. When a file name referencing a data object is deleted, the data objectís reference count is decremented by one. The data object itself only gets deleted when the reference count is decremented to zero.
The reference count is the only way of determining whether there are multiple file name references to a data object, and it only informs of their number NOT there whereabouts.
Junctions are wormholes in the tree structure of a directed graph. By browsing a Junction a maybe far distant location in the file system is made available. Modifying, Creating, Renaming and Deleting files within a junction tree structure operates at the junction target, i.e. if you delete a file in a Junction it is deleted at the original location.

Symbolic Links are to files what Junctions are to folders in that they are both transparent and Symbolic. Transparency means that an application can access them just as they would any other file, Symbolism means that the data objects can reside on any available volume, i.e. they are not limited to a single volume like Hardlinks. Symbolic Links differ from Shortcuts in that they offer a transparent pathway to the desired data object, with a shortcut (.lnk), something has to read and interpret the content of the shortcut file and then open the file that it references (i.e. it is a two step process). When an application uses a symlink it gains immediate access to the data object referenced by the symlink (i.e. it is a one step process).


There is a way explained to see via the file's properties if it references something

I have no idea if this even applys to your question, but hopefully it will help a little

Paul

Cyberdude
01-24-2010, 12:44 PM
The Win 7 file system and Windows Explorer displays . . . Arrrrrrrgh!

Paul, the two references shown in your reply to me DO answer a LOT of questions I've had. Every serious Win 7 user should be required to read them, but not necessarily understand them! How can Microsoft possibly consider these changes to the file system as an improvement over what they were using??

I think I'll change my "Don't show hidden files" back to "Leave them hidden". Unhiding them serves only to complicate the Windows Explorer display unnecessarily.

Thanx a million for your reply, Paul! :friends:
Sid