Prof. Powershell

Tee Off

Tee-Object -- a slight variation on the Out-File cmdlet.

• By Jeffery Hicks
• 05/07/2008

PS C:\> get-service | where {$_.status -ne "Running"} | Tee NotRunning.txt

When you run this command, PowerShell will display the results to the console and save them to the text file NotRunning.txt.

The Tee-Object cmdlet does not have the same parameters as Out-File, so you can't have the output be appended or prevent a previous file from being overwritten. You also can't specify the encoding type. However, you can use an input object as in these two examples:

PS C:\> $p = get-process

PS C:\> tee myprocs.txt -input $p

Remember that $p is a collection of process objects. The objects are formatted before being written to the text file, myprocs.txt. But because $p is an object, we could use expressions like these:

PS C:\> tee topten.txt -input ($p | sort cpu -desc | select -first 10)

PS C:\> tee proc.txt -input $p[0..4]

The first example sorts the contents of $p by CPU in descending order and then selects the first 10 processes. The second example simply outputs the first 5 processes in $p.

If you've been using PowerShell for a little bit, you will realize these expressions could also be written like these ones:

PS C:\> $p | sort cpu -desc | select -first 10 | tee topten.txt

PS C:\> $p[0..4] | tee proc.txt

The net result is the same in either. Which format to use will depend on your PowerShell needs at the time. I expect you'll more often use the latter format, but I wouldn't rule out a complex script or function where the first example would be easier to use.