CODEWITHSUNDEEP
powershell
PortMan
PortMan

Reputation: 4523

Can't get failing script to return exit code

I’ve got a simple powershell script like this:

Set-Strictmode -version Latest
$ErrorActionPreference = 'Stop'

try
{
  Write-Host "aaa $(MyFunc "bbb)"
}
catch
{
  Write-Host "Caught the error!"
  Write-Host $error
  exit 666
}

(Note that this script has an error in the first Write-Host line.)

I need my scripts to run in such a way that if there are any errors, it will return with a non-zero value. This is the purpose of setting “Set-Strictmode”, “$ErrorActionPreference”, and wrapping it all in a try…catch block.

But when I run it from the windows cmd.exe, you can see that the error is not caught and that it does not return an error code:

D:\jjj>powershell -F jjj.ps1
At D:\jjj\jjj.ps1:6 char:28
+   Write-Host "aaa $(MyFunc "bbb)"
+                            ~~~~~
The string is missing the terminator: ".
At D:\jjj\jjj.ps1:6 char:34
+   Write-Host "aaa $(MyFunc "bbb)"
+                                  ~
Missing closing ')' in subexpression.
    + CategoryInfo          : ParserError: (:) [], ParentContainsErrorRecordException
    + FullyQualifiedErrorId : TerminatorExpectedAtEndOfString

D:\jjj>echo Exit Code is %errorlevel%
Exit Code is 0

I suspect that the unmatched quotes in the errorful line is mangling the interpretation so much that the try…catch block is never properly instantiated.

So, here’s the question: what can I do to ensure that any execution errors of my PowerShell script cause it to return with a non-zero errorcode?

Upvotes: 0

Views: 1563

Answers (1)

Ansgar Wiechers
Ansgar Wiechers

Reputation: 200203

You have a syntax error there, not a runtime error. There's nothing you can do except actually fixing it. Syntax errors can't be caught at runtime, because they occur when PowerShell parses the code, i.e. before the instructions actually get executed.

If you run the script from within PowerShell the automatic variable $? will be set to $false, though. If you run it in a new powershell process like this:

powershell "C:\path\to\your.ps1"

the errorlevel ($LASTEXITCODE in PowerShell) will be set to 1 on errors. Unfortunately the errorlevel is not set when you run the script using the -File parameter:

powershell -File "C:\path\to\your.ps1"

which you'd normally do to have regular exit codes from the script returned to the caller.

Upvotes: 4

Related Questions