Running a build script after calling vcvarsall.bat from powershell - c

Question

I am attempting to run the Visual Studio (developer cmd prompt) environmental variable setup batch file followed by a build script from within a Powershell script as follows:
cmd /v:on/k "(""C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\vcvarsall.bat"" amd64_x86 && C:\buildscript.cmd --build-options)"
It appears however that the environmental settings established by vcvarsall.bat are not retained for the build script call. i.e. no default compiler setup, etc.
Is the /v:on combined with the /k switch not actually utilizing the same cmd session and properly delaying environmental variable expansion? Perhaps the approach is wrong ...

Answer 1

The problem is that when you run cmd.exe to run a batch file, the variables are set in that instance of cmd.exe, but they disappear after that instance terminates.
To work around this problem, you can use the Invoke-CmdScript function in this article:
Windows IT Pro: Take Charge of Environment Variables in PowerShell
The function is as follows:
# Invokes a Cmd.exe shell script and updates the environment.
function Invoke-CmdScript {
param(
[String] $scriptName
)
$cmdLine = """$scriptName"" $args & set"
& $Env:SystemRoot\system32\cmd.exe /c $cmdLine |
select-string '^([^=]*)=(.*)$' | foreach-object {
$varName = $_.Matches[0].Groups[1].Value
$varValue = $_.Matches[0].Groups[2].Value
set-item Env:$varName $varValue
}
}
You could add this function to your PowerShell profile or use it as a script file.
Once you have defined the function, you can run your commands:
Invoke-CmdScript "C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\vcvarsall.bat" amd64_x86
C:\buildscript.cmd --build-options
...or whatever you need.
The article also presents a couple of functions that let you easily save and restore environment variables.