Name
S line
Synopsis
Each mail message must have a sender. The sendmail program can determine the sender in four ways:
If the sender is specified in the envelope of an SMTP connection, that sender’s address is used.
If the
-f
command-line argument is used to run sendmail, the sender’s address is the address following the-f
.If the sender is not specified in the envelope, the address that is used is that of the user who ran the sendmail program. If that user is unknown, the sender is made to be postmaster.
When processing the queue, the sender’s address is specified in the
S
line of theqf
file.
The form of the S
line in the
qf
file looks like this:
Saddr
The S
must begin the line. Exactly one address
must follow on that same line. Whitespace can surround that address.
There can be only one S
line in the
qf
file.
If the addr
is missing,
sendmail sets the sender to be the user who ran
sendmail. If that user is not known in the
passwd file (or database),
sendmail syslog(3)s the
following message and sets the sender to be
postmaster:
Who are you?
The resulting address is then processed to extract the
user’s full name into $x
($x). Finally, the sender’s
address is rewritten by the canonify
rule set 3,
the parse
rule set 0, and the
final
rule set 4.
Under all versions of sendmail the address in
the S
line will include any RFC822 comment text
that appeared with the original message. Under V8.7, if the
F=c
flag (F=c) is set for the sender’s delivery agent, all comment text is stripped from ...
Get Sendmail, 3rd Edition now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.