[Matplotlib-users] [OT] Confusion with mailing lists

[Robert D. <rcd...@gm...>]

Hey guys,

I realize this isn't the place to post this but I can't figure out a better
place. I just had a really quick question.

Sometimes I notice that mail I receive from this mailing list was never
directly (through To: or CC:) sent to the mailing list. For example, say
there's two people communicating:

fo...@bl...
fo...@bl...

Usually when foo1 sends a mail to foo2, foo2 will receive a mail like this:

To: fo...@bl...
From: fo...@bl...
CC: mat...@li...

However, in one case I found that the mail was never sent to
matplotlib-users. However, somehow the list.sourceforge.net mailing server
intercepted it and sent it to the other person via a 'bounce' email address.
How does this happen? What are the different ways one could send an email to
a mailing list?

Thanks, and again apologies for the off topic post.