Apologies if this has been addressed before, I couldn't find it:
I want to add my app's directory (my app is a set of command line tools) to the PATH environment variable, i.e. concatenate the
directory name to the end of the existing value "Path" of the registry key "Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Environment".
Ideally also, not adding it if it is already there, and removing it during uninstall.
I can see how to add new values, but I am not sure how to concatenate a string to the end of an existing value.
Thanks for your help!