     Mail sent by the send_mail "command" goes into the recipient's mailbox,
and the recipient reads it from there with the read_mail command.  The
read_mail command works interactively, that is, instead of taking all
information from you on the "command line," it prompts you for more
information and direction as you go.

     In addition to reading mail, the read_mail command can be used to save
mail, reply to mail, forward mail, and discard mail.  All of this is done by
issuing "requests" when you are asked for input by the prompt 'read_mail:'.
When you issue the read_mail command, it tells you how much mail is
in the mailbox and, if there is some, immediately asks you to provide more
information.  For example, when you type:

read_mail

the following message and prompt will be returned:

You have one message.

read_mail:

At this point you can request to read the mail with the print request, print
a summary with the list request, or a number of other things with the
appropriate requests.  One of those things is to ask for a summary of the
requests by typing a question mark (?).

     The read_mail command automatically reads from your regular mailbox
unless you specify another mailbox by way of an "argument" to the command.
For example:

read_mail high_priority

     You can also go to another mailbox from within read_mail by using the
execute request.  This request, whose short name is e, treats the rest of
the line like a command.  So, if in response to a prompt you type:

read_mail: e read_mail high_priority

you will go into the mailbox named high_priority.

     To see this command in action, go to "command level" by pressing the
function key F2.  Then type the read_mail command.  When you are prompted,
type the list request; it will list all of your messages, unless you specify
particular messages by number.  Then try using a few of the other requests,
such as the question mark (?) and print.  Whenever you are ready to return to
the Tutorial, leave read_mail by typing the quit request in response to a
prompt and then type pi when you've returned to command level.
