Passing selected multiple file names to the single instance of an exe file via Windows 10's Context menu

Question

I have written a script in python 3.8 that takes two file names as command-line args and does some operations. And now I wish to add the .exe file of that script to Windows 10's context menu. I manually added an entry to the registry under "HKEY_CLASSES_ROOT*\\shell\\MY_APP\\command" but what it does is, execute the .exe file twice instead of taking them as multiple parameters to a single instance of my app.

Ask:

1. How can I make it execute only once by-passing multiple selected file names as parameters to a single app instance?
2. How can I build an installer that adds an entry to the registry automatically when the user is installing my app?

Thank you

Answer 1

The classic static verb registration you are doing here is always going to launch multiple instances.

There are two possible workarounds:

• Implement IExplorerCommand orIDropTarget COM shell extensions.

• When your application is started, try to find another instance already running and pass it the new path with some kind of IPC, for example the WM_COPYDATA message.