Windows 10: I Need Some Powershell Education

X.bat should clear the console screen, like cls, and that’s all it will do. It will not change the current directory because .bat files will be executed as a sub process in cmd.exe (as the %cmdcmdline% batch variable will reveal to you), if that’s what you mean by “doesn’t work”.

It’s just another program, really.

 

I had expected X.bat to "exit" the shell and return me to the desktop like it does when ran in Command Prompt. But now, thanks to your tutelage I have a much better understanding what PS is & does.

Thank you for your time. It is much appreciated. Enjoy your weekend.

 

Not sure what you mean by "doesn't work". Does it execute and give you different results than you expect? Or does it not execute at all and give an error message?

You need to be aware that batch files will spawn a separate CMD process and run, which means it will execute the above statements, but the Exit statement will exit the CMD process, leaving you back at the powershell process.

To be frank, I'm not even sure why you would have such a batch script, since even in a normal command prompt all those actions will be performed and then the command prompt goes away.. you could have just aliased X to Exit and it would do the same thing, the stuff that comes before it are pointless.

 

They do not execute, no error message or anything else. The X.bat was created because typing "x" was shorter than "exit" to leave command prompt.

No big deal and certainly not an "issue" or problem.

 

To read PATH variable in PowerShell:
$envath
(#1 in screenshot.)

-- OR --

Read it directly from registry:
Get-ItemProperty 'Registry::HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Environment' -Name PATH
(#2 in screenshot.)




(Click to enlarge.)

To add a folder in PATH, we need first read current path from registry to a variable (in this example I will use variable $CurrentPath, you can use any variable name you prefer), then write $CurrentPath plus folder we want to add to path to another variable (I will now use $ModifiedPath), and finally replace path in registry with modified path.

Read current path to variable $CurrentPath:
$CurrentPath=(Get-ItemProperty 'Registry::HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Environment' -Name PATH).Path

Add a folder (D:\MyScripts in this example) to path, write new path to variable $ModifiedPath:
$ModifiedPath=$CurrentPath+';D:\MyScripts'

Write new path to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Environment\Path
Set-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Environment' -Name PATH -Value $ModifiedPath





Notice that PowerShell does not show new path yet. You need to close PS and open a new session to see changes.

 

Yeah, and using an alias for Exit is also just typing a single X.

Powershell will give you an error if it's not executing, so in fact, it did execute, you just didn't see anything (because of the @ECHO OFF). You can see this by altering your batch file to remove the Exit, and you will see you are still in a CMD shell, and not in a Powershell (there won't be a PS at the beginning). Then type Exit and you will see it returns to the PS prompt.

Another tell-tale sign is to do a DIR in the CMD prompt vs in Powershell, the output will be different.

 

Yip, that's the way to access those... I don't think the registry route is advisable (for various reasons)

Anyway.. there is a site called scripting guy or something that dedicate themselves to this stuff...

 

These last three posts are terrific! Hadn't even considered a couple of things here. Thank you all.