December 2002
Intermediate to advanced
1232 pages
56h 38m
English
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Name
F=w
Synopsis
The sendmail program
uses the getpwnam(3) routine (and can use
others, such as LDAP) to determine whether a local address
corresponds to a local account. If it does, the home directory for
the user is copied into $z ($z). Then the full name of the user is extracted
from the GECOS field of the passwd(5) file and
placed into $x ($x).
Beginning with V8.7 sendmail, the information in
the passwd(5) file is looked up only if the
F=w delivery agent flag is set for the
recipient’s delivery agent. In general, it must be
present (set) for the local and any local-clone
delivery agents but should be absent for all other delivery agents.
For configuration files of levels lower than 6 (Section 17.5), the F=w delivery agent
flag is automatically set for the local delivery
agent.
Omitting the F=w delivery agent flag has several
consequences:
The recipient’s home directory is not looked up, and all user-level forwarding is prevented. Note that this voids all forwarding, even if the user’s home is defined as part of the
ForwardPathoption (ForwardPath).The user’s full name is not looked up in the GECOS field of the passwd(5) file (the setting of the
MatchGECOSoption, MatchGECOS, is ignored).The user-id and group-id of the recipient become unavailable, so the identity of the controlling user cannot be set to that of the recipient.
Note that if you are using Unix V7-style mailboxes (as with
/bin/mail), this delivery agent flag should be
considered mandatory for local and local clones. ...
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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.