I asked for a first explanation "here" and "here" but going to try a more complex situation I was unable (after two hours of trying) to understand how to solve. I read how the regular expression works but nothing, I went into the ball.

The modified code is this:

(Fsutil Dirty Query %SystemDrive%>Nul)||(powershell.exe -c "[Environment]::CommandLine; Start -Verb RunAs cmd /k, ("^""%~f0"^"" -replace '[;,()= &^]', '^$&')" & echo exit)

and the folder with the poison characters is this:

C:\Users\fposc\Desktop\Pie & tea % @ ' $^

I have tried to escape the ^ in the regular expression with \^ but don't work. I have escaped also ( and ) with \( and \). But nothing work:

(Fsutil Dirty Query %SystemDrive%>Nul)||(powershell.exe -c "[Environment]::CommandLine; Start -Verb RunAs cmd /c, ("^""%~f0"^"" -replace '[;,\(\)= &\^]', '^$&')" & exit)

I added the round brackets because I wanted to put all possible characters to make the code as generic as possible.

I don't know if I was right to open another question. Maybe I should change the original question? Since other combinations are possible and not having understood the mechanism I could open many other similar questions. What do you advise me to do?

CodePudding user response：

The problem is the presence of $ in your folder name, which causes the PowerShell command to interpret it as the start of a variable reference.

The workaround is to use an aux. environment variable to store the batch file's full path and let PowerShell perform its escaping based on this variable's value:

:: Unless already elevated, re-invoke this batch file with elevation,
:: via PowerShell.
set "__THISFILE=%~f0"
Fsutil Dirty Query %SystemDrive% >Nul || (powershell.exe -c "Start-Process -Verb RunAs cmd /k, ($env:__THISFILE -replace '[ &%%^]', '^$&')" & exit)

I have updated the answer to your original question to incorporate this approach, which now shows a - hopefully - robust approach to on-demand re-invocation of a batch file with elevation, including support for arguments.