December 2002
Intermediate to advanced
1232 pages
56h 38m
English
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Name
F=A
Synopsis
Prior to V8.7
sendmail, only the local
delivery agent could cause addresses to be looked up in the
aliases(5) database (Section 12.1.2). Beginning with V8.7
sendmail, any delivery agent that has an
F=A delivery agent flag set will cause its
$: address to be looked up on the lefthand side of
the aliases(5) file.
For example, the F=A delivery agent flag can be
used to design a local-clone delivery agent that recognizes certain
nonlocal addresses as local for aliasing purposes:[26]
R$+ <@ FIRE.WALL> $#firelocal $: $1@fire.wall
This allows an alias file such as the following to legally exist:
George.Washington@fire.wall: gw@internal.net
For example, as a safety net (and if the F=5
delivery agent flag is also specified), any address that is not found
in the aliases(5) database will be passed to the
localaddr rule set 5 (Section 19.6), where another delivery agent can be
selected.
In configuration files prior to Version 6 (Section 17.5), the F=A delivery agent
flag is automatically set for the local delivery
agent.
[26] This example is somewhat contrived because the same thing can
be done in a more versatile manner with the
mailertable feature (FEATURE(mailertable)).
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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.