On Sat, 8 Sep 2001, L.D. Best wrote:
> Excuse the hell outta me. I'm tired, I have FMS and sometimes get
> things mixed up.
>
> First: abend is a term I picked up while helping with programs for
> BigBlue mainframes; it means abort/end
> i.e. not the way something is supposed to end.
Never having worked at BigBLue, I wouldn't have
known that. Neither would anyone else on this list.
We could only surmise what you must have meant.
> Second: I meant RedHat Linux, not Apache. My ISP uses Apache with
> RedHat.
We're not mind-readers. Apache and Red Hat are
totally unrelated to each other. In this case it
would have been impossible to even guess that you
really meant something other than what you wrote.
(though Red Hat isn't involved in the evolution
of POP3 either)
> Third: SMTP doesn't store messages, POP3 does.
POP3 does not store messages. At your ISP, the
mail is stored by the Mail Delivery Agent.
POP3 is not a delivery agent... it is a protocol.
> And the way they are
> stored *has* changed from single flatfile to index & database. If you
> don't believe me, see if you can get one of the techies at my ISP to
> explain it to you better.
As I said, if your ISP has something weird, then
more details are needed.
In *MY* RedHat Linux, the MTA (what you refer to
as SMTP) is sendmail v.8.9.3-20. That is, it sends
mail, and it receives mail. Once sendmail receives an
e-mail, it hands it off to procmail to check for
unwanted content, spammers, executables, even if the
mail is from the arachne list. Procmail then delivers
the e-mail to the spamfolder, arachne directory,
my regular mailbox, or in some cases, into the bit
bucket.
In my situation then, it is procmail which acts
as the delivery agent. It adds new e-mail to the
end of the /var/spool/mail/steve file, the
/home/steve/mail/arachne file, the
/home/steve/mail/spamfolder file, or to a special
kind of "file" called /dev/null.
There are no databases used anywhere in e-mail
storage... in Red Hat Linux 4.x, 5.x, or 6.x.
> Fourth: Unless/until you believe what I say in Third item above,
> there's no sense in generating a response.
Of course there is. What you say in Third item
above is completely wrong. Generating a response
might help you to better understand how e-mail
really works.
An e-mail author uses a Mail User Agent to write
e-mail. This can be Netscape, PINE, elm, etc.
The MUA uploads the message (via the SMTP protocol)
to the Mail Transfer Agent.
The MTA sends the mail to the MTA at the recipient's
ISP, where it either stores the mail in the user's
mailbox directly, or hands it off to a Mail Delivery
Agent for delivery to the mailbox. In some cases the
same program can act as both MTA and MDA, though
often the two functions are performed by separate
programs.
Using sendmail and/or mail, the e-mail is appended
to a file in /var/spool/mail/username, while qmail,
functioning as both MTA and MDA, delivers mail to the
home directory ($HOME/Mailbox).
Now, the e-mail is sitting in the user's mailbox on
his ISP. The user can login to his ISP and read the
mail directly in any of a number of ways, or he can
use an MUA to download mail (via POP3) to his own
machine. His e-mail will be stored on his hard drive
in any number of ways, according to whatever MUA is
used.
To give you some food for thought: If you send an
e-mail to [EMAIL PROTECTED], there will not be
ANY POP3 involved ANYWHERE in getting the message from
you to me.
> Fifth: All of that aside, regardless of how anything is stored anywhere
> on the POP3 server, I'd still like the POP3.log file generated to be a
> full capture, and not just a message [and message comand] log. Only
> that way can problems be pinpointed.
No disagreement there.
You might find further clarification at this page:
http://www.sendmail.org/email-explained.html
- Steve
