[c++] Get a file name from a path

shlwapi.lib/dll uses the HKCU registry hive internally.

It's best not to link to shlwapi.lib if you're creating a library or the product does not have a UI. If you're writing a lib then your code can be used in any project including those that don't have UIs.

If you're writing code that runs when a user is not logged in (e.g. service [or other] set to start at boot or startup) then there's no HKCU. Lastly, shlwapi are settlement functions; and as a result high on the list to deprecate in later versions of Windows.