December 2002
Intermediate to advanced
1232 pages
56h 38m
English
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Name
$h
Synopsis
The parse rule set 0 (Section 19.5) is used to resolve the recipient address into
a triple: the delivery agent (with $#), the host
part of the address (with $@), and the recipient
address (with $:). The host part, from the
$@, is made the value of $h.
Once $h’s value has been set, it
undergoes no further rule-set parsing.
$h is intended for use in the
A= equate (A=) of
delivery agent definitions. Normally, it is converted to all
lowercase before use, but that conversion can be suppressed with the
F=h delivery agent flag (F=h).
$h is also used by the
localaddr rule set 5 (Section 19.6) to process +detail
addresses (Section 12.4.4).
$h is transient. If it is defined in the
configuration file or in the command line, that definition can be
ignored by sendmail. Note that a
$& prefix is necessary when you reference this
macro in rules (that is, use $&h, not
$h).
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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.