PowerShell Tee to console in a pipeline

Question

I generate a csv file :

myscript.ps1 | Export-Csv result.csv

but it's a slow process and I'd like to see progress. I thought Tee-Object would do it but I'm looking for a 'Tee to console' effect which Tee-Object doesn't seem to offer?

If I do

myscript.ps1 | Write-Host | Export-Csv result.csv

that destroys the objects. How can I Tee-Host ?

In short, as of PowerShell 7+ `Tee-Object` actually is able to output to the console, by using the special file names `CON` (Windows) or `/dev/tty` on *nix systems. — zett42, Aug 19 '22 at 12:48
Applied to your case: `myscript.ps1 | tee CON | Export-Csv result.csv` — zett42, Aug 19 '22 at 13:08
alas I have to stay with PS5.1 since that's what's on my colleagues' desktops — Chris F Carroll, Aug 19 '22 at 14:07

score 3 · Answer 1 · answered Aug 19 '22 at 11:32

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Use ForEach-Object:

myscript.ps1 |ForEach-Object { $_ |Out-Host; $_ } |Export-Csv ...

answered Aug 19 '22 at 11:32

Mathias R. Jessen

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This is tempting, but applying `Out-Host` to _individual_ objects will result in unexpected table formatting, as each object will be in its own table, with its own header. Try `$result = Get-ChildItem / | % { $_ | Out-Host; $_ }` To solve that problem, a proxy function is needed. However, in PowerShell (Core) 7+ you can simply pipe to `Tee-Object ($IsWindows ? 'CON' : '/dev/tty')` – mklement0 Aug 19 '22 at 14:05

Tom · Accepted Answer · 2022-08-19T23:45:42.673

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Mathias has answered exactly what you asked, but as an alternative I'd suggest using write-progress as a way of getting a visual indication of how a task is progressing.

edited Aug 19 '22 at 23:45

answered Aug 19 '22 at 11:34

Tom

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to be fair, you did answer what I said I wanted — a progress report :-) – Chris F Carroll Aug 20 '22 at 14:21

PowerShell Tee to console in a pipeline

2 Answers2