-command's exit code is not the same as a script's exit code

Question

I need to run a script with PowerShell -Command "& scriptname", and I would really like it if the exit code I got back from PowerShell was the same as the exit code the script itself returned. Unfortunately, PowerShell returns 0 if the script returns 0, and 1 if the script returns any non-zero value as illustrated below:

PS C:\test> cat foo.ps1
exit 42
PS C:\test> ./foo.ps1
PS C:\test> echo $lastexitcode
42
PS C:\test> powershell -Command "exit 42"
PS C:\test> echo $lastexitcode
42
PS C:\test> powershell -Command "& ./foo.ps1"
PS C:\test> echo $lastexitcode
1
PS C:\test>

Using [Environment]::Exit(42) almost works:

PS C:\test> cat .\baz.ps1
[Environment]::Exit(42)
PS C:\test> powershell -Command "& ./baz.ps1"
PS C:\test> echo $lastexitcode
42
PS C:\test>

Except that when the script is run interactively, it exits the whole shell. Any suggestions?

Answer 1

If you look at the part you are sending to -Command as a script you will see it would never work. The script running the foo.ps1 script does not have a call to exit, so it does not return an exit code.

If you do return an exit code it will do what you want. Also change it from " to ', otherwise $lastexitcode will be resolved before you 'send' the string to the second PowerShell, if you run it from PowerShell.

PS C:\test> powershell -Command './foo.ps1; exit $LASTEXITCODE'
PS C:\test> echo $lastexitcode
42

PS: Also check out the -File parameter if you just want to run a script. But also know it does not return 1 if you have a terminating error as -Command does. See here for more on that last topic.

PS C:\test> powershell -File './foo.ps1'
PS C:\test> echo $lastexitcode
42