Viewing Junctions with ‘dir’

re: Viewing Junctions with ‘dir’

JFX — Mon, 01 Aug 2011 00:53:57 GMT

I agree with L. and Jon ... maybe in version 3 ?

re: Viewing Junctions with ‘dir’

jon — Wed, 10 Mar 2010 06:50:36 GMT

@L.

I agree. PowerShell really ought to support for listing and manipulating junctions, hard links and symlinks out of the box.

re: Viewing Junctions with ‘dir’

L. — Sun, 14 Feb 2010 22:43:43 GMT

@PowerShellTeam: Come on, you should support current NTFS features out of the box! Even cmd.exe knows about junctions and symlinks.

@Nigel Sharples [MSFT]: This will display a J for any kind of reparse point, though, not only for junctions. Is it really all right to confuse junctions with e.g. files moved to offline storage? (IIRC reparse points are used in this case to trigger fetching back the file).

@n4cer: You description of junctions vs symlinks is right, but junctions are not hard links. Hard links are yet another kind of beast (a file that has several names, possibly in different directories), and are also supported by NTFS.

re: Viewing Junctions with ‘dir’

n4cer — Thu, 11 Feb 2010 07:16:06 GMT

@FP - Junctions are hard links, evaluated on the server in networking scenarios, and available in NT since Windows 2000.

Symbolic links, introduced on Windows in Windows Vista along with support for them in SMB2, are soft links and evaluated clientside.

Both link types are implemented using NTFS reparse points.

The equivalent to ln on Windows Vista and above is mklink. On versions prior to Vista, you can use linkd (shipped seperately in a Resource Kit) or the Sysinternals tool linked in the post.

Reparse points can also be shown in CMD's dir using the /AL switch, and in Vista/7's Explorer if the related columns are made visible.

re: Viewing Junctions with ‘dir’

Klaus Graefensteiner — Wed, 10 Feb 2010 20:25:16 GMT

This is great stuff. I am working with Junctions a lot. Every deployment of our software needs to change junction points.

Klaus

re: Viewing Junctions with ‘dir’

Blake — Wed, 10 Feb 2010 10:15:57 GMT

This works, but it is not a good practice, because the it leaves the impression that the Mode property includes that trailing J when it doesn't.

The better practice is to add a new ScriptProperty to a local types.ps1xml file for both DirectoryInfo and FileInfo types. Mine looks like this:

<Name>Attrib</Name>

if ($this.Attributes -band [IO.FileAttributes]::ReparsePoint) {

'l'+$this.Mode

} else {

'-'+$this.Mode

}

</GetScriptBlock>

</ScriptProperty>

Then use a local format.ps1xml to display that property for table formatting rather than the Mode property.

(I used an 'l' to mirror the unix-y look of the rest of usual Mode string, because ReparsePoint can be set for many things other than a directory junction, and because 'r' is already used.)

re: Viewing Junctions with ‘dir’

FP — Wed, 10 Feb 2010 07:57:07 GMT

Oh, so if I understand correctly, "junctions" are just like the soft links Unix has had for, what, 30 years ? Where is the ln utility ? And why on Earth is it necessary to copy and paste (!) code from the equivalent of "ls" to see that some items are in fact soft links ?