[prog] Mailing list software - how does the emailing work? (mass bcc?)

[Dan]

> As you may now know I'm taked with custom developing mailing list
> software from scratch with no knowledge of how to do this and very
> little guideance (an invididual project which ~12 people are doing).

I'm assuming that you're doing this as a project for school, right?
Unless you're doing it for your own enrichment, I strongly recommend
using existing mailing list software. Mailman is an excellent example of
a full-featured mailing list. If you want to actually hack the code,
Majordomo might be a good choice because it's smaller.

The traditional way to make mailing lists is to use alias files:
  http://www.uwsg.iu.edu/usail/mail/aliasing/
The link documents Sendmail alias files but I think that most other SMTP
servers support them.

However, nothing prevents you from doing a massive BCC, which is what an
alias file ultimately does anyway. I recommend researching the SMTP
protocol. Don't be afraid to try out what you've learned:
  $ telnet localhost 25
  Trying 127.0.0.1...
  Connected to localhost.localdomain.
  Escape character is '^]'.
  220 localhost.localdomain ESMTP Exim 4.50 Tue, 03 May 2005 12:00:22
+0100
  HELO dan
  250 localhost.localdomain Hello dan at localhost [127.0.0.1]
  QUIT
  221 localhost.localdomain closing connection
  Connection closed by foreign host.

A massive BCC (or an alias file) is the most efficient solution. Looping
through the addresses is less efficient but is also an option,
especially if you want to customize content for each recipient.

> I think there are limits from when you have too higher number
> that you would be considered to be spamming people.

That depends on how you allow the mailing list to be used. Normally only
the owner of an address can subscribe that address (this is what
LinuxChix does), and in that case you don't have to worry about abuse.
Don't be afraid of big mailing lists: even if thousands of people are
subscribed to a list, you are not a spammer as long as the people chose
to be on the list and can unsubscribe whenever they want. However,
mailing lists (including LinuxChix) often allow only subscribers to
post, to avoid spam from random address harvesters.

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