Some files contain lines that begin with
the five characters "
" (the fifth character is a space).
What happens to such lines when the files containing them are delivered
to a local mailbox?
What UNIX utilities
are available to aid in sending such a file with those lines
In the file
, we created a one-line header that
What would be the effect of making
that header all lowercase? What does RFC822
have to say about this?
(See "Additional Sources of Information" in
behave when it is given a message that
contains only a header? Does it add a blank line to create
an empty body?
If your MUA supports a
(verbose) command-line switch,
try to send mail to someone at a remote machine using that switch.
You should be able to observe the actual conversation between
and a remote machine's
If you can, send mail addressed both to yourself on the local machine and
to yourself on a remote machine. Compare and contrast the header part
If you are at all fuzzy about the concept of envelope,
Section 1.7, "The Envelope"
now. We will refer to envelopes often
throughout this tutorial.
Leap ahead to
for additional information about specific headers.