Powershell: running JScript scripts without logo - powershell

Question

I set cscript.exe as my default scripting host with the nologo option. Therefore in cmd.exe
I get, as expected:
> ftype jsfile
jsfile="C:\Windows\System32\CScript.exe" //nologo "%1" %*
> reg query HKCR\jsfile\Shell\Open\Command
HKEY_CLASSES_ROOT\jsfile\Shell\Open\Command
(Default) REG_EXPAND_SZ "C:\Windows\System32\CScript.exe" //nologo "%1" %*
> echo WScript.Echo("Test Echo"); > test.js
> test.js
Test Echo
But, moving to Powershell:
> powershell -nologo
PS > .\test.js
Microsoft (R) Windows Script Host Version 5.8
Copyright (C) Microsoft Corporation. All rights reserved.
Test Echo
It seems that CScript does not get //nologo from Powershell shell.
How can I fix this?
More use cases
It also works with:
PS > cscript.exe //nologo test.js
Test Echo
PS > cmd /c test.js
Test Echo
PS > cmd /c test
Test Echo
Copy & Paste Test
Someone suggests it can be a bug. To check if it applies to you, you can copy the following in a PS console with elevated privileges:
## Change the host to cscript nologo and store old setting
$jstype="Registry::HKEY_CLASSES_ROOT\jsfile\Shell\Open\Command"
$jsvalue=("`"$env:SystemRoot\System32\CScript.exe`"" + ' //nologo "%1" %*')
$old=(gp -Path $jstype )."(default)"
Set-Item -Path $jstype -value $jsvalue
## The output should be the same (i.e. nologo!)
echo 'WScript.Echo("Test Echo");' > test.js
cmd /c test
.\test.js
## Restore old settings
Set-Item -Path $jstype -value $old
Is cmd /c test and .\test.js output the same?

Answer 1

Details on the problem
It seems that Powershell has a weird behaviour with respect to file associations.
If you paste the following snippet in an elevated privilege PS shell:
$jstype="Registry::HKEY_CLASSES_ROOT\jsfile\Shell\Open\Command"
Set-Item -Path $jstype -value "cscript.exe total non sense"
echo 'WScript.Echo("Test Echo");' > test.js
cmd /c test.js
... you get the deserved error for associating jsfiles with the command string cscript.exe total non sense.
But surprisingly writing:
.\test.js
works like a charm. So it seems that PS only reads the first item of the open-command-string (here cscript.exe) and then appends to it the user string (.\test.js), totally disregarding the other elements of the open-string, here total non sense.
To confirm paste this:
Set-Item -Path $jstype -value "notepad.exe total non sense"
echo 'WScript.Echo("Test Echo");' > test.js
cmd /c test.js
cmd.exe opens the Notepad which proposes to create the file "total non sense.txt".
Now write:
.\test.js
Based on what I just said, the actual command run will be notepad.exe .\test.js and in fact the Notepad will now open .\test.js.
Solution
Whether or not this is a bug, a possible solution is to create a batch script calling the cscript.exe with the desired parameters. I will name it C:\Windows\System32\cscript.cmd.
To create the script and the related association, paste:
echo "#cscript.exe //nologo %*" | out-file -encoding ASCII C:\Windows\System32\cscript.cmd
$jstype="Registry::HKEY_CLASSES_ROOT\jsfile\Shell\Open\Command"
$jsvalue=("`"$env:SystemRoot\System32\cscript.cmd`"" + ' "%1" %*')
Set-Item -Path $jstype -value $jsvalue
As you see //nologo is moved from the registry to cscript.cmd.
Note that echo "string" > would produce a Unicode file, which cmd.exe dislikes, hence the ASCII filter.
Print your new .js opening command:
cmd /c ftype jsfile
That is: jsfile="C:\Windows\System32\cscript.cmd" "%1" %*.
Now both:
cmd /c test
.\test
will produce:
Test Echo
without the banner, and note that in both cases you don't need to specify the .js extension.
For simplicity I set cscript.cmd to run cscript.exe straight. You might want to specify its full path.