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Mychaela Falconia <falcon@freecalypso.org>
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1 The present code repository contains email software which Mother Mychaela
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Mychaela Falconia <falcon@freecalypso.org>
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2 developed for her own personal use; it is unlikely to be of interest to other
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Mychaela Falconia <falcon@freecalypso.org>
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3 people as my tastes in personal technology tend to be very different from the
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Mychaela Falconia <falcon@freecalypso.org>
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4 rest of the world, but I publish almost all of my software nonetheless, as a
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Mychaela Falconia <falcon@freecalypso.org>
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5 matter of general principle.
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Mychaela Falconia <falcon@freecalypso.org>
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6
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Mychaela Falconia <falcon@freecalypso.org>
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7 The main program in the present collection is f-demime - it is a de-MIME-ing
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Mychaela Falconia <falcon@freecalypso.org>
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8 tool. f-demime processes one or more email messages in UNIX mailbox format
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Mychaela Falconia <falcon@freecalypso.org>
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9 (each message preceded and delimited by a '^From ' line) and applies the
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Mychaela Falconia <falcon@freecalypso.org>
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10 following transformations to each message:
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Mychaela Falconia <falcon@freecalypso.org>
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11
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Mychaela Falconia <falcon@freecalypso.org>
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12 1] base64 blobs that aren't text parts are excised from the message; each such
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Mychaela Falconia <falcon@freecalypso.org>
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13 blob is decoded and saved into its own file. These saved attachment files
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Mychaela Falconia <falcon@freecalypso.org>
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14 are written into a special directory that must be indicated with
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Mychaela Falconia <falcon@freecalypso.org>
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15 FDEMIME_ATT_DIR= environment variable.
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Mychaela Falconia <falcon@freecalypso.org>
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16
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Mychaela Falconia <falcon@freecalypso.org>
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17 2] text/plain parts that are encoded in either base64 or quoted-printable are
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Mychaela Falconia <falcon@freecalypso.org>
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18 decoded and written out in a form that (a) losslessly preserves the content
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Mychaela Falconia <falcon@freecalypso.org>
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19 of the text part that originally contained non-ASCII characters and/or
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Mychaela Falconia <falcon@freecalypso.org>
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20 insanely long lines, but also (b) is more suitable for direct consumption by
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Mychaela Falconia <falcon@freecalypso.org>
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21 my wetware, rather than MIME software. The output form uses backslash
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Mychaela Falconia <falcon@freecalypso.org>
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22 escapes to represent non-ASCII characters and machine-inserted line breaks.
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Mychaela Falconia <falcon@freecalypso.org>
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23
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Mychaela Falconia <falcon@freecalypso.org>
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24 3] text/html and other non-plain text parts that are encoded in base64 are
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Mychaela Falconia <falcon@freecalypso.org>
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25 losslessly transcoded from base64 to quoted-printable.
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Mychaela Falconia <falcon@freecalypso.org>
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26
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Mychaela Falconia <falcon@freecalypso.org>
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27 The transformations applied by f-demime aren't fully lossless at level of
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Mychaela Falconia <falcon@freecalypso.org>
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28 overall message lines and octets (one cannot take f-demime output and
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Mychaela Falconia <falcon@freecalypso.org>
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29 reconstruct a message byte-identical to the original), but they are lossless at
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Mychaela Falconia <falcon@freecalypso.org>
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30 the level of content which MIME itself promises to preserve.
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Mychaela Falconia <falcon@freecalypso.org>
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31
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Mychaela Falconia <falcon@freecalypso.org>
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32 One important demiming function which f-demime does NOT do is collapsing
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Mychaela Falconia <falcon@freecalypso.org>
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33 multipart/alternative structures, keeping text/plain and discarding HTML. The
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Mychaela Falconia <falcon@freecalypso.org>
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34 rationale for this functional omission is that I will be inserting f-demime
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Mychaela Falconia <falcon@freecalypso.org>
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35 into my incoming mail handling path, such that every incoming message will
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Mychaela Falconia <falcon@freecalypso.org>
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36 automatically pass through f-demime before it hits my eyeballs. Given the
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Mychaela Falconia <falcon@freecalypso.org>
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37 current state of badness on the Internet, I occasionally receive mails in which
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Mychaela Falconia <falcon@freecalypso.org>
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38 the HTML part (which would be thrown away in a multipart/alternative collapse)
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Mychaela Falconia <falcon@freecalypso.org>
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39 contains some valuable or interesting information content that is missing in the
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Mychaela Falconia <falcon@freecalypso.org>
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40 text/plain version - thus fully automatic collapsing is not a workable approach
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Mychaela Falconia <falcon@freecalypso.org>
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41 currently. I plan on implementing another program (resurrecting maltcollapse
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Mychaela Falconia <falcon@freecalypso.org>
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42 from my previous cdemime attempt circa 2006) to do this multipart/alternative
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Mychaela Falconia <falcon@freecalypso.org>
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43 collapsing, and then devising a practical way to invoke it once I have
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Mychaela Falconia <falcon@freecalypso.org>
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44 determined that the HTML part is junk that can be safely thrown away.
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