Messages - A Multi-Media Mailer

In this article, Terry Gliedt continues his tour through the Andrew project—this time into a new area, multi-media mail.
Messages

Messages is actually just one part of a larger system known as the Andrew Mail System. This system supports reading and posting to bulletin boards and delivery between cells in the Andrew File System. I will not discuss any of these topics here, but rather just describe messages as a conventional mail user agent.

To view your mail, invoke the command messages from an xterm window. In Figure 1 you can see that the resulting messages window has three parts. The top window shows a list of folders where you can save mail. The folder “mail” is where your incoming mail is saved until you move it elsewhere or delete it. When you use messages the first time, your only folder will be a mail folder. To begin, select a folder (probably mail) by pointing to a name and clicking with the left mouse button.

The middle window will now display a summary of the mail in that folder. Select one of these and you'll see the summary line in bold and, in the bottom window, the text of the message. In Figure 1 you will notice several things. The headers of the mail (From:, To:, etc.) are show in bold. When you delete a piece of mail, the summary line is changed to a smaller font, but the actual file is not deleted until you explicitly delete it. More discerning eyes will notice the scroll bar shows that there is something above the From: line. This data is the normal mail headers which you normally do not want to see. If you look at the headers for this particular piece of mail, you'd see that it has the lines:

     MIME-Version: 1.0
     Content-Type: multipart/alternative;
        boundary="Interpart.Boundary.ohyS2z9z0001I1RlEF"

indicating this is MIME mail and consists of several parts. If you look at the summary line for this mail, you'll notice the phrase “(60+1)”, meaning the body consists of 60 characters and contains one inset.

In the body of the mail, you can see the phrase “Information SuperHighway” is in a larger bold font. MIME's metamail or another low-end MIME reader would convert this to simple text on systems which do not have font capabilities. On some systems the picture might show up in a separate window. Since messages has all the capabilities of AUIS, the text and images are shown in-line, as they were intended.

Sending Mail

To compose and send mail to someone, select Send/Post Message on the messages menucard. This will present a window as shown in Figure 2. In many ways, this is just another ez session. (ez is the basic editor in AUIS and was described in issue 4 of Linux Journal.) In this particular example, I selected the mail we saw in Figure 1 and then I selected Reply to Sender on the messages menucard. This brought up the messages-send window with the Subject: and To: fields already filled out. I then selected the first sentence of the original mail (so it was shown in reverse video) and then in the messages-send window, selected Excerpt body on the Other menucard. This resulted in the indented and italized Excerpts lines that you see.

Had we not marked any text and simply selected this menu card, the entire original message body would have been copied, indented and italized.

Notice that the excerpted area may contain more than simple text, for example the large, bolded Information SuperHighway. In fact we could have also included the image you saw in Figure 1. To send the mail, select Send/Post on the messages-send menucard. If the mail contains multi-media (anything except simple plain ASCII text), you will be prompted as shown in Figure 3. If you select Remove formatting and send, messages will do some simple text conversion. The excerpt will have the font information removed and the excerpt text itself will be prefixed with “>” as is common with many mail readers. As you can see in Figure 3, you may choose to send the mail in the original AUIS format or in MIME format. You can avoid the question altogether and always send in MIME format with an entry in your $HOME/preferences file like this:

     *.mailsendingformat: mime

Issue the command auishelp preferences and read about the mailsendingformat setting for more information.

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