December 2002
Intermediate to advanced
1232 pages
56h 38m
English
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Name
$=t
Synopsis
Trusted
users are those who can run sendmail with the
-f command-line switch to specify who sent the
message, without generating a warning. Prior to V8.6
sendmail, such users had to be listed with the
T command (Section 10.8.1.1). That
command was ignored in V8.1 through V8.6, and with those versions
anyone could use the -f switch. Beginning with
V8.7 sendmail, the T command
was reintroduced, but it now causes the list of trusted users to be
added to the class $=t. Now, any user who uses the
-f switch and who is not listed in class
$=t will cause the following error message (X-Authentication-Warning:) to be included in the outgoing mail message
(if the PrivacyOptions option, PrivacyOptions, has authwarnings set):
X-Authentication-Warning: user set sender to other using -f
See the use_ct_file feature (FEATURE(use_ct_file)) for an easy way to add users to this class
using the m4 technique.
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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.