How to add Install Directory Path to Registry?

I want to add the install directory path to the registry.
So if the user installs into C:\Program Files\Test App
I want Path "C:\Program Files\Test App" added to the registry HKEY_LOCAL_MACHINE\SOFTWARE\Test App

I've searched the forums and all i can find is how to lookup the install path not add it to the registry

WriteRegStr HKLM "Software\Test App" "Path" "$INSTDIR"

"Path" can be replaced with anything value of your choosing.

Superb - worked perfectly 😉
Thanks for your help

And you can use InstallDirRegKey to have the installer automatically read that value.

Stu