Private/LinkUtil.ps1
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function Resolve-PathForced { <# .SYNOPSIS Calls Resolve-Path but works for files that don't exist. .REMARKS From http://devhawk.net/2010/01/21/fixing-powershells-busted-resolve-path-cmdlet/ #> param ( [string] $FileName ) $FileName = Resolve-Path $FileName -ErrorAction SilentlyContinue ` -ErrorVariable _frperror if (-not($FileName)) { $FileName = $_frperror[0].TargetObject } return $FileName } function Remove-Symlink { <# .SYNOPSIS Removes a symbolic link. #> param ( [Parameter(Position=0, Mandatory=$true)] [string] $Link ) # Remove-Item cannot be used to remove symbolic link to directory as it # will remove the content of the directory it points to. [System.IO.Directory]::Delete($Link, $true) } function New-Symlink { <# .SYNOPSIS Creates a symbolic link. #> param ( [Parameter(Position=0, Mandatory=$true)] [string] $Link, [Parameter(Position=1, Mandatory=$true)] [string] $Target, [Parameter(Position=2)] [switch] $Force ) Invoke-MKLINK -Link $Link -Target $Target -Symlink -Force $Force } function New-Hardlink { <# .SYNOPSIS Creates a hard link. #> param ( [Parameter(Position=0, Mandatory=$true)] [string] $Link, [Parameter(Position=1, Mandatory=$true)] [string] $Target, [Parameter(Position=2)] [switch] $Force ) Invoke-MKLINK -Link $Link -Target $Target -HardLink -Force $Force } function New-Junction { <# .SYNOPSIS Creates a directory junction. #> param ( [Parameter(Position=0, Mandatory=$true)] [string] $Link, [Parameter(Position=1, Mandatory=$true)] [string] $Target, [Parameter(Position=2)] [switch] $Force ) Invoke-MKLINK -Link $Link -Target $Target -Junction -Force $Force } function Invoke-MKLINK { <# .SYNOPSIS Creates a symbolic link, hard link, or directory junction. #> [CmdletBinding(DefaultParameterSetName = "Symlink")] param ( [Parameter(Position=0, Mandatory=$true)] [string] $Link, [Parameter(Position=1, Mandatory=$true)] [string] $Target, [Parameter(ParameterSetName = "Symlink")] [switch] $Symlink = $true, [Parameter(ParameterSetName = "HardLink")] [switch] $HardLink, [Parameter(ParameterSetName = "Junction")] [switch] $Junction, [Parameter()] [bool] $Force ) # Resolve the paths incase a relative path was passed in. $Link = (Resolve-PathForced $Link) $Target = (Resolve-PathForced $Target) # Ensure target exists. if (-not(Test-Path $Target)) { throw "Target does not exist.`nTarget: $Target" } # Ensure link does not exist. if (Test-Path $Link) { if ($Force) { Remove-Item $Link -Recurse -Force } else { throw "A file or directory already exists at the link path.`nLink: $Link" } } $isDirectory = (Get-Item $Target).PSIsContainer $mklinkArg = "" if ($Symlink -and $isDirectory) { $mkLinkArg = "/D" } if ($Junction) { # Ensure we are linking a directory. (Junctions don't work for files.) if (-not($isDirectory)) { throw "The target is a file. Junctions cannot be created for files.`nTarget: $Target" } $mklinkArg = "/J" } if ($HardLink) { # Ensure we are linking a file. (Hard links don't work for directories.) if ($isDirectory) { throw "The target is a directory. Hard links cannot be created for directories.`nTarget: $Target" } $mkLinkArg = "/H" } # Capture the MKLINK output so we can return it properly. # Includes a redirect of STDERR to STDOUT so we can capture it as well. $output = cmd /c mklink $mkLinkArg `"$Link`" `"$Target`" 2>&1 if ($lastExitCode -ne 0) { throw "MKLINK failed. Exit code: $lastExitCode`n$output" } else { Write-Verbose $output } } function mklink { <# .SYNOPSIS Helper function for calling mklink directly. All arguments are piped through to mklink. Hat tip to http://stackoverflow.com/questions/894430/powershell-hard-and-soft-links#comment9823010_5549583 #> cmd /c mklink $args } |