Select directory from a file - windows

Question

I need my program to give me every folder containing files which are out of the Windows' number of characters limit. It means if a file has more than 260 characters (248 for folders), I need it to write the address of the file's parent. And I need it to write it only once. For now, I'm using this code:
$maxLength = 248
Get-ChildItem $newPath -Recurse |
Where-Object { ($_.FullName.Length -gt $maxLength) } |
Select-Object -ExpandProperty FullName |
Split-Path $_.FullName
But the Split-Path won't work (this is the first time I use it). It tells me the -Path parameter has a null value (I can write -Path but it doesn't change anything).
If you want an example of what I need: imagine folder3 has a 230-character address and file.txt has a 280-character address:
C:\users\folder1\folder2\folder3\file.txt
Would write:
C:\users\folder1\folder2\folder3
I'm using PS2, by the way.

Answer 1

Spoiler: the tool you are building may not be able to report paths over the limit since Get-ChildItem cannot access them. You can try nevertheless, and also find other solutions in the links at the bottom.
Issue in your code: $_ only works in specific contexts, for example a ForEach-Object loop.
But here, at the end of the pipeline, you're only left with a string containing the full path (not the complete file object any more), so directly passing it to Split-Path should work:
$maxLength = 248
Get-ChildItem $newPath -Recurse |
Where-Object { ($_.FullName.Length -gt $maxLength) } |
Select-Object -ExpandProperty FullName |
Split-Path
as "C:\Windows\System32\regedt32.exe" | Split-Path would output C:\Windows\System32
Sidenote: what do (Get-Item C:\Windows\System32\regedt32.exe).DirectoryName and (Get-Item C:\Windows\System32\regedt32.exe).Directory.FullName output on your computer ? These both show the directory on my system.
Adapted code example:
$maxLength = 248
Get-ChildItem $newPath -Recurse |
Where-Object { ($_.FullName.Length -gt $maxLength) } |
ForEach-Object { $_.Directory.FullName } |
Select-Object -Unique
Additional information about MAX_PATH:
How do I find files with a path length greater than 260 characters in Windows?
Why does the 260 character path length limit exist in Windows?
http://www.powershellmagazine.com/2012/07/24/jaap-brassers-favorite-powershell-tips-and-tricks/
https://msdn.microsoft.com/en-us/library/windows/desktop/aa365247%28v=vs.85%29.aspx
https://gallery.technet.microsoft.com/scriptcenter/Get-ChildItemV2-to-list-29291aae

Answer 2

you cannot use get-childitem to list paths greater than the windows character limit.
There are a couple of alternatives for you. Try an external library like 'Alphafs' or you can use robocopy. Boe Prox has a script that utilizes robocopy and it is available on technet but i am not sure if it will work on PSV2. Anyway you can give it a try.

Answer 3

I've had a similar problem and resolved it like this:
$PathTooLong = #()
Get-ChildItem -LiteralPath $Path -Recurse -ErrorVariable +e -ErrorAction SilentlyContinue
$e | where {$_.Exception -like 'System.IO.PathTooLongException*'} | ForEach-Object {
$PathTooLong += $_.TargetObject
$Global:Error.Remove($_)
}
$PathTooLong
On every path that is too long, or that the PowerShell engine can't handle, Get-ChildItem will throw an error. This error is saved in the ErrorVariable called e in the example above.
When all errors are collected in $e you can filter out the ones you need by checking the error Exception for the string System.IO.PathTooLongException.
Hope it helps you out.