Writing errors and output to a text file and Console

Question

I am trying to write the entire output (errors included) of an executing script to the console and a file at the same time. I have tried several different options:

Answer 1

I wasn't satisfied with any answer I was finding, so I mixed a few and came up with this (in PowerShell 3.0+):

$output = try{your_command *>&1}catch{$_}

With this you can capture all errors and output that are generated by trying to use your_command.

It catches exceptions when you use a non-existent command:

PS C:\Users\jdgregson> $output = try{your_command *>&1}catch{$_}
PS C:\Users\jdgregson> echo $output
your_command : The term 'your_command' is not recognized as the name of a
cmdlet, function, script file, or operable program. Check the spelling of the
name, or if a path was included, verify that the path is correct and try again.
At line:1 char:15
+ $output = try{your_command 2>&1}catch{$_}
+               ~~~~~~~~~~~~
    + CategoryInfo          : ObjectNotFound: (your_command:String) [], Comman
   dNotFoundException
    + FullyQualifiedErrorId : CommandNotFoundException

PS C:\Users\jdgregson>

It catches exceptions when you pass invalid arguments to an existing command:

PS C:\Users\jdgregson> $output = try{cat C:\invalid-path.txt *>&1}catch{$_}
PS C:\Users\jdgregson> echo $output
cat : Cannot find path 'C:\invalid-path.txt' because it does not exist.
At line:1 char:15
+ $output = try{cat C:\invalid-path.txt 2>&1}catch{$_}
+               ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : ObjectNotFound: (C:\invalid-path.txt:String) [Ge
   t-Content], ItemNotFoundException
    + FullyQualifiedErrorId : PathNotFound,Microsoft.PowerShell.Commands.GetCo
   ntentCommand

And it catches the output if there was no problem with your command at all:

PS C:\Users\jdgregson> $output = try{cat C:\valid-path.txt *>&1}catch{$_}
PS C:\Users\jdgregson> echo $output
this file is really here

It works for your example too:

PS C:\Users\jdgregson> $output = try{Test-Error *>&1}catch{$_}
PS C:\Users\jdgregson> echo $output
echo
WARNING: warning
Test-Error : error
At line:1 char:15
+ $output = try{Test-Error *>&1}catch{$_}
+               ~~~~~~~~~~~~~~~
    + CategoryInfo          : NotSpecified: (:) [Write-Error], WriteErrorExcep
   tion
    + FullyQualifiedErrorId : Microsoft.PowerShell.Commands.WriteErrorExceptio
   n,Test-Error