how to set difference between reply and bounce email

Question

im building system, that tracks bounce emails and also when user reply back with message, then other user can read the message of this user.

so far i have read from all the questions / answers, that bounce email can be sent to return-path or also to reply-to path.

how can i tackle this issue? should i scan and see if its bounce email, if its not, then consider it as message email or there is some other way around it?

checking for bounce email and then parsing for message, its just extra overhead, when system is getting lots and lots of emails from bounce or as messages.

Answer 1

Bounce should be sent back to address given in From while for replies you can provide alternate address in Reply-To header. So if you set two different addresses there (ie. From: bounce@... and Reply-To: reply@...., and process mails arriving