Reading the message from business transaction to custom program

Hi everyone,

I am having an issue where I need to read the message after saving. So, the requirement is that via our custom program, it should use the call transaction to open a business transaction, and after the user saves the data in the transaction, it will return back in our custom program. In the custom program, I have the below successful message 'Equipment plan * is saved':

How can I read this message that comes in my custom program, as I need to use the value of the equipment plan in a latter point?

Also, I cannot use BDC as the user needs to input the values by himself.

Thank you all in advance!

R