The F=F delivery agent
flag is used by sendmail.cf header commands to
force the inclusion of sender
("From")
information (F=):
H?F?Re-sent-From: $q
H?F?From: $q
The F=F delivery agent flag has no special
internal meaning to sendmail. It is a convention
that is used only in the assorted
"From:" header
definitions (From:). See F= for a general description of this process.
