These are the notes for lecture 9 Mark -- Today's fortune: The future isn't what it used to be. (It never was.)Title: Math 481/581 Lecture 9: MIME
This document discusses the basics of MIME encoded email.
Specifically, we'll cover composing and sending MIME encoded messages using Netscape, and reading MIME messages with the Pine mailer.
If you choose to send people MIME encoded mail, remember to consider your recipient: this person will need to have the necessary software to decode your encoded message!
Sending MIME encoded messages with Netscape is pretty easy. From the File menu, select "New Mail Message". A new window will pop up where you can type in the text of your message, the recipients, etc.
To attach a text file, HTML file, image, etc. to the message, click on the "Attach..." button. To attach a file, click the appropriate button and follow your nose until you're done.
Once you have finished composing your message, click "Send". That's it!
>From hays Mon Sep 28 08:06:58 1998 Return-Path: <hays> Received: (from hays@localhost) by dec.math.arizona.edu (8.8.5/8.8.5) id IAA09271 for hays; Mon, 28 Sep 1998 08:06:57 -0700 (MST) Received: from sahuarita.math.arizona.edu by dec.math.arizona.edu (fetchmail-4.3.2 POP3 run by hays) for <hays@localhost> (single-drop); Mon Sep 28 08:06:57 1998 Received: from amethyst.math.arizona.edu (amethyst.math.arizona.edu [188.8.131.52]) by sahuarita.math.arizona.edu (8.9.0.Beta5/8.9.0.Beta5) with ESMTP id IAA12352 for <firstname.lastname@example.org>; Mon, 28 Sep 1998 08:05:47 -0700 (MST) Received: from dec.math.arizona.edu (dec.math.arizona.edu [184.108.40.206]) by amethyst.math.arizona.edu (8.9.0.Beta5/8.9.0.Beta5) with SMTP id IAA08066 for <hays>; Mon, 28 Sep 1998 08:05:52 -0700 (MST) Sender: email@example.com Message-ID: <360FA5FF.41C6@math.arizona.edu> Date: Mon, 28 Sep 1998 08:06:39 -0700 From: Mark Hays <firstname.lastname@example.org> Organization: Department of Mathematics, Univ. of Arizona X-Mailer: Mozilla 3.0 (X11; I; OSF1 V3.2 alpha) MIME-Version: 1.0 To: email@example.com Subject: A Simple MIME message Content-Type: multipart/mixed; boundary="------------167E2781446B" X-UIDL: d6360199912e3903592e716d6e86e868 Status: RO X-Status: X-Keywords: X-UID: 1 This is a multi-part message in MIME format. --------------167E2781446B Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit This is a simple MIME message -- it contains a picture. Happy Viewing! Mark --------------167E2781446B Content-Type: image/gif; name="home.gif" Content-Transfer-Encoding: base64 Content-Disposition: inline; filename="home.gif" R0lGODlhPAARAMQAAP///xAQECEhITExMTk5OUJCQkpKSlJSUlpaWmtra3Nzc3t7e4yMjJSU lJycnK2trbW1tb29vcbGxs7OztbW1t7e3u/v797e5wAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA ACwAAAAAPAARAAAF/yAgjmRpnmiqrmzrvnBMWk6CIIljybxrQQeBcHCA7GKFRU/lEBwakokD IXDIkksURbCoUCQR8EJQQSocXRFNB7gsIg0GLQ2gLKykhMEyifghgDhIARAIGBUVAQwNARUS GAgPARgQAwIADgEPB0ojVRdhfxFolzBYjxEKAyIDChEYEgAFBQALGAACSVQkARcTYBGAEA4K AUhKrxEHtLIGqLK0trgIEmC8FH7BEA8PDQjGpsiwmRYWAQ7JAATRt2MVFhQkBAwTwg/DCwUE MWcAEwUTas1SQoFAPAUKMDFzcODAAxIMBth7gIYKgywYR1wg8KRBHAUHBhC4kLGkhAJEDhYY GBCgQKySJSt4u5GgAUmYOHPqzBgCADs= --------------167E2781446B--The first Content-Type line looks like:
Content-Type: multipart/mixed; boundary="------------167E2781446B"This line says that the message body consists of several parts, each with its own Content-Type. The parts of the message body are separated with the string "------------167E2781446B" on a line by itself.
The first part of the message simply states that the message is MIME encoded.
The second part is plain text -- this part is the text I typed into the Netscape message composition window.
The third and final part is a GIF image encoded in base 64. In base 64, 3 bytes of binary data are encoded as 4 bytes of ASCII data. The base 64 "digits" are:
In order to read this message in a meaningful way (to be able to see the GIF image, for example), you will need to use a MIME-enabled mail reader.
If you read this message with Berkeley Mail, you will see the message exactly as shown above (because Mail doesn't know about MIME).
I will also assume that you do not read mail with Netscape. Netscape (irreversibly, more or less) converts all of your mail into HTML. Most other mail programs store mail in standard UNIX "mbox" format, which allows these programs to interoperate with one another. For example, you can use a graphical mail program while in X windows and a terminal based mail program when logged in from home.
If you use Netscape, you are locked into it because other mail programs assume that your mailbox is in mbox format.
Instead, I will assume that you normally use Berkeley Mail and that you have received a MIME encoded message that you want to view. The first step is to save the message to a file using Mail's "s" command:
& s mimeThis will create a file named "mime" which contains the raw message in mbox format (as in the example above).
Next, get out of Mail using "q" or "x".
Pine stores your mail folders in
will need to create this directory if it doesn't already exist.
If you already have a file or directory called "mail", you'll
need to temporarily rename it and create a new directory for
Next, move the file "mime" into the "mail" directory and start up pine on the message:
> mkdir mail > mv mime mail > pine -f mimeFollow your nose until you are reading the message. At this point, your screen will look something like:
PINE 3.96 MESSAGE TEXT Folder: mime Message 1 of 1 ALL Date: Mon, 28 Sep 1998 08:06:39 -0700 From: Mark HaysAs you can see, Pine knows that the message contains a GIF, but it cannot display it directly on the terminal. If you follow Pine's hint and hit the "V" key (in uppercase), your screen will look like this:
To: firstname.lastname@example.org Subject: A Simple MIME message Parts/attachments: 1 Shown 4 lines Text 2 OK 412 bytes Image ---------------------------------------- This is a simple MIME message -- it contains a picture. Happy Viewing! Mark [Part 2, Image/GIF 550bytes] [Not Shown. Use the "V" command to view or save this part] [ALL of message] ? Help M Main Menu P PrevMsg - PrevPage D Delete R Reply O OTHER CMDS V ViewAttch N NextMsg Spc NextPage U Undelete F Forward
PINE 3.96 ATTACHMENT INDEX Folder: mime Message 1 of 1 1 4 lines Text/PLAIN 2 412 bytes Image/GIF ? Help E Exit Index P PrevAttch - PrevPage A AboutAttch V [View] N NextAttch Spc NextPage S Save W WhereIsIf you aren't in an X windows session, you probably won't be able to display the GIF at all. In such a case, you can save the image to a file by hitting the "S" key.
Assuming that you are in X windows, and that
(or the systemwide mailcap file) contains a line like:
image/*; xv %syou can view the image using the "xv" image viewer by selecting the GIF attachment and pressing the
RETURNkey. Hit the "q" key in the xv window to quit xv.
When you are done viewing attachments, hit "E" to get back to the message list, followed by "Q" to quit Pine.
If you receive an attachment that your mailer doesn't understand, the best you can do is to save it to a file and take it somewhere else. This will likely be the case if you receive an MSWord document on a UNIX system, for example.