The C= delivery agent
equate (introduced with V8.7 sendmail) is used
to define a default character set for use with the MIME
Content-Type: header (Content-Type:). If it is present, its value supersedes that
of the DefaultCharSet option (DefaultCharSet).
Note that the C= delivery agent equate is examined
only when the delivery agent is selected for an envelope sender
address.
When a mail message is converted from 8 to 7 bits (see the
EightBitMode option in EightBitMode), it is important that the result looks like a
MIME message. V8.7 sendmail first outputs the
following header (if one is not already present):
MIME-Version: 1.0
Next, V8.7 sendmail looks for a
Content-Type: header (Content-Type:). If none is found, the following is inserted,
where charset is the value declared for
the C= delivery agent equate of the
sender's delivery agent:
Content-Type: text/plain; charset=charset
If the argument to C= is missing, the following
error is printed and C= becomes undefined:
mailer agent_name: null charset
If the C= delivery agent equate is undefined in
your configuration file, charset defaults
to the value of the DefaultCharSet option. If both
are undefined, the value for charset
becomes unknown-8bit.
