I am working on a PHP based mailing list using PHPmailer.
Currently I have implemented two options for answers to mailing list posts: reply to sender only Vs reply to list. This basically controls which address is inserted in the Reply-To field.
I want to create the behaviour which my users know from Mailman, here an example:
SenderA posts a message:
From: senderA@foo.bar
To: list@foo.bar
The mailing list forwards it to all recipients, e.g. here to RecipientA:
From: senderA@foo.bar
To: recipientA@foo.bar
CC: list@foo.bar
Now RecipientA replies to the post and the reply looks like that:
From: recipientA@foo.bar
To: senderA@foo.bar
The other option RecipientA has is posting the reply to the whole mailing by choosing "reply to all" in the mail client which looks like that in the reply:
From: recipientA@foo.bar
To: senderA@foo.bar
CC: list@foo.bar
When I would decide to set the mailing list's address in the CC field for all forwarded mails:
Does that mean the mail comes back to the mailing list 100 times when I send out the mail to 100 subscribers (-> it would cost quite a lot of performance to retrieve, check and drop that duplicate mails)
Can I include a certain header so that the mail to the CC'd mailing list is not send 100 times? How can I tell the mail server(s) to not do that?
Or:
- Is there an alternative way to allow the users to decide to reply to the sender or to the whole list?