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Creating hard and soft links using PowerShell

Can PowerShell 1.0 create hard and soft links analogous to the Unix variety?

If this isn't built in, can someone point me to a site that has a ps1 script that mimics this?

This is a necessary function of any good shell, IMHO. :)

Windows 10 users see stackoverflow.com/a/34905638/195755 . Windows 10 it is built-in. Copy/Paste: New-Item -Type and press tab to cycle through the options. Hardlink, SymbolicLink, and Junction appear for me. Works Win 10, Server 2016+, or older OS with Powershell 5.0+ installed via Windows Management Framework 5.0+.
I can't find decent MSDN/TechNet documentation for New-Item -Type HardLink nor New-Item -Type SymbolicLink. New-Item docs link to help about_Providers, it suggests you read help for each provider (which isn't linked). But if you google it there is plenty of buzz in the PowerShell community around New-Item -Type HardLink. It looks like the PowerShell engineering team has come up with provider extension points that stump the docs team.
WARNING! -- While it is very easy to create hardlinks, it may be quite a challenge to remove them securely. That is because the tools are not easily available in native Powershell while Windows like to lock file access and keep files in memory (thus not always removable without a reboot.) Please see my post here.

M
Martin Schneider

Windows 10 (and Powershell 5.0 in general) allows you to create symbolic links via the New-Item cmdlet.

Usage:

New-Item -Path C:\LinkDir -ItemType SymbolicLink -Value F:\RealDir

Or in your profile:

function make-link ($target, $link) {
    New-Item -Path $link -ItemType SymbolicLink -Value $target
}

Turn on Developer Mode to not require admin privileges when making links with New-Item:

https://i.stack.imgur.com/1HYya.png


This link is now broken due to MS rearranging documentation. I found a current working link at technet.microsoft.com/en-us/library/hh849795.aspx
New-Item -Path C:\LinkDir -ItemType SymbolicLink -Value F:\RealDir
since Windows v1703, mklink allows creating symlinks without account elevation, if Developer mode is enabled in Settings, New-Item doesn't. Hopefully in next update.
With the accepted answer, I was able to use relative paths, which wasn't the case with the New-Item commandlet.
New-Item allows an -ItemType of HardLink for a file and Junction for a directory. These do not require developer mode or admin privileges.
D
Dave F

You can call the mklink provided by cmd, from PowerShell to make symbolic links:

cmd /c mklink c:\path\to\symlink c:\target\file

You must pass /d to mklink if the target is a directory.

cmd /c mklink /d c:\path\to\symlink c:\target\directory

For hard links, I suggest something like Sysinternals Junction.


If you have a powershell profile, you can also make a quick function function mklink { cmd /c mklink $args }
and if you want to make a directory link, the command will be something like { cmd /c mklink /D "toDir" fromDir }
adding the /H parameter to mklink will create a hard link without the need for a third party program like Sysinternals Junction.
I think jocassid has the better answer. IMHO, We should try to teach how to USE PowerShell, not use exploits and hacks through cmd.exe.
C
Community

Add "pscx" module

No, it isn't built into PowerShell. And the mklink utility cannot be called on its own on Windows Vista/Windows 7 because it is built directly into cmd.exe as an "internal command".

You can use the PowerShell Community Extensions (free). There are several cmdlets for reparse points of various types:

New-HardLink,

New-SymLink,

New-Junction,

Remove-ReparsePoint

and others.


Good try. Though if you want to run XP or W2K3 server in either x32 or x64, New-Symlink dosen't work. In XP it will politely tell you that you should be running Vista for this command. In W2K3 server, it flat out breaks.
That's because XP doesn't support symlinks. That's a feature new to Vista. I believe that W2K3 server doesn't support symlinks either. You have to step up to W2K8 server to get symlink support. I'll look into why new-symlink is bombing on W2k3, it should error with a similar message to XP.
I tried new-junction and that will work for me. Too bad the link functionality doesn't degrade to junctions in XP and W2K3
on further use of new-junction... I get a junction to the new parse point. However ls (or get-childitem) errors stating that.."The filename, directory name, or volume label syntax is incorrect" If I try and enter a subdirectory from there.
Windows 10 users see answer stackoverflow.com/a/34905638/195755 . Windows 10 it is built-in. Copy/Paste: New-Item -Type and press tab to cycle through the options. Hardlink, SymbolicLink, and Junction appear for me. Works Win 10, Server 2016+, or older OS with Powershell 5.0 installed via Windows Management Framework 5.0+.
q
quigi

In Windows 7, the command is

fsutil hardlink create new-file existing-file

PowerShell finds it without the full path (c:\Windows\system32) or extension (.exe).


fsutil hardlink requires new-file and existing-file to be on the same drive. If that matters to you, use cmd's mklink /c instead.
@mopsled Hardlinks, by definition, must be on the same volume as the target, this is not a limitation specific to fsutil (or Windows for that matter)
is there an equivalent for "soft" symlinks and junctions?
Worked also on a Windows10 system.
b
bviktor

New-Symlink:

Function New-SymLink ($link, $target)
{
    if (test-path -pathtype container $target)
    {
        $command = "cmd /c mklink /d"
    }
    else
    {
        $command = "cmd /c mklink"
    }

    invoke-expression "$command $link $target"
}

Remove-Symlink:

Function Remove-SymLink ($link)
{
    if (test-path -pathtype container $link)
    {
        $command = "cmd /c rmdir"
    }
    else
    {
        $command = "cmd /c del"
    }

    invoke-expression "$command $link"
}

Usage:

New-Symlink "c:\foo\bar" "c:\foo\baz"
Remove-Symlink "c:\foo\bar"

Windows 10 users see stackoverflow.com/a/34905638/195755 . Windows 10 it is built-in. Copy/Paste: New-Item -Type and press tab to cycle through the options. Hardlink, SymbolicLink, and Junction appear for me. Works Win 10, Server 2016+, or older OS with Powershell 5.0 installed via Windows Management Framework 5.0+.
Or if the file name contains them.
C
Community

Try junction.exe

The Junction command line utility from SysInternals makes creating and deleting junctions easy.

Further reading

MS Terminology: soft != symbolic Microsoft uses "soft link" as another name for "junction". However: a "symbolic link" is something else entirely. See MSDN: Hard Links and Junctions in Windows. (This is in direct contradiction to the general usage of those terms where "soft link" and "symbolic link" ("symlink") DO mean the same thing.)


The use of this utility correctly allows me to junction another directory and traverse it's subdirectories successfully. All in XP and W2K3. Just add the exe to a directory in your PATH and call it like normal.
I don't think you can use junction.exe to create symbolic links.
It´s better to use mklink which is shipped with Windows. If you have a Windows version which it is shipped with.
P
Peter Mortensen

I combined two answers (@bviktor and @jocassid). It was tested on Windows 10 and Windows Server 2012.

function New-SymLink ($link, $target)
{
    if ($PSVersionTable.PSVersion.Major -ge 5)
    {
        New-Item -Path $link -ItemType SymbolicLink -Value $target
    }
    else
    {
        $command = "cmd /c mklink /d"
        invoke-expression "$command ""$link"" ""$target"""
    }
}

P
Peter Mortensen

You can use this utility:

c:\Windows\system32\fsutil.exe create hardlink

It will require elevated privileges, though. Creating hardlinks usually doesn't.
j
joshuapoehls

I wrote a PowerShell module that has native wrappers for MKLINK. https://gist.github.com/2891103

Includes functions for:

New-Symlink

New-HardLink

New-Junction

Captures the MKLINK output and throws proper PowerShell errors when necessary.


P
Peter Mortensen

Actually, the Sysinternals junction command only works with directories (don't ask me why), so it can't hardlink files. I would go with cmd /c mklink for soft links (I can't figure why it's not supported directly by PowerShell), or fsutil for hardlinks.

If you need it to work on Windows XP, I do not know of anything other than Sysinternals junction, so you might be limited to directories.


S
Steven

I found this the simple way without external help. Yes, it uses an archaic DOS command but it works, it's easy, and it's clear.

$target = cmd /c dir /a:l | ? { $_ -match "mySymLink \[.*\]$" } | % `
{
    $_.Split([char[]] @( '[', ']' ), [StringSplitOptions]::RemoveEmptyEntries)[1]
}

This uses the DOS dir command to find all entries with the symbolic link attribute, filters on the specific link name followed by target "[]" brackets, and for each - presumably one - extracts just the target string.


Is this an answer for a different question?