December 2002
Intermediate to advanced
1232 pages
56h 38m
English
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The Symbolic Delivery Agent Name
The M
that begins the delivery agent definition command is immediately
followed, with no intervening whitespace, by the name of the delivery
agent. Note that the name is symbolic and is used only internally by
sendmail. The name can contain no whitespace,
and if it is quoted, the quotation marks are interpreted as part of
its name. In the following, only the first is a good symbolic name:
Mlocal ← name is local, good M local ← error: name required for mailer Mmy mailer ← error: mailer my: `=' expected M"mymailer"← quotation marks are retained
Although the symbolic name can contain any character other than a space or a comma, only letters, digits, dashes, and underscore characters are recommended:
Mprog-mailer ← name is prog-mailer, good Mprog_mailer ← name is prog_mailer, good Mmymailer[ ]; ← name contains [ ];—avoid such characters
The symbolic name is not case-sensitive; that is,
local, Local, and
LOCAL are all identical.
Note that if two delivery agents have the same name, all the delivery agent equates for the second definition replace those for the first. Therefore, the last definition for a particular symbolic name is the one that is used.
The cumulative result of all delivery agent declarations can be seen
by using the -d0.15 debugging switch (-d0.15) or the =M rule-testing
command (Section 8.4.2).
Required Symbolic Names
Only the local delivery
agent is required,[2] so if that
required definition is missing, sendmail prints the following warning ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.