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<H2><a name="archives">Archives</a></H2>

<!--X-TOC-Start-->
<ul>
<li><a href="#split">Why does a message get split into mulitple messages with no headers?</a></li>
<li><a href="#move">Can I move a message from one archive to another?</a></li>
<li><a href="#reconstruct">Can I reconstruct a database from the HTML messages?</a></li>
<li><a href="#dynamic">Is it safe to add messages to an archive as they are received?</a></li>
<li><a href="#forward">So it is safe.  How do I do it??</a></li>
<li><a href="#majordomo">How can I do it with Majordomo lists?</a></li>
<li><a href="#different">Can I get MHonArc to filter messages to different archives?</a></li>
<li><a href="#exclude">Does MHonArc support the "no archive" flag in messages?</a></li>
<li><a href="#addsafe">Is it safe to specify <tt>-add</tt> when no archive exists?</a></li>
<li><a href="#jumps">Why are there "jumps" in message numbers?</a></li>
<li><a href="#dups">Why do some messages get re-added each time MHonArc processes a mail folder?</a></li>
<li><a href="#remove">How do I remove messages from an archive?</a></li>
<li><a href="#tombox">Can I convert an archive back to mailbox format?</a></li>
</ul>
<!--X-TOC-End-->

<!-- ??????????????????????????????????????????????????????????????? -->
<hr noshade size=1>
<table border=0>
<tr valign=top><td><img src="monicon.png" align="bottom" alt=""></td><td>
<h3><b><a name="split">Why does a message get split into mulitple messages with no headers?</a></b></h3>
</td></tr></table>

<P>If you are processing UUCP mailbox files, messages are
separated by a line starting with "<code>From </code>" (ie. The
word "<code>From</code>" followed by a space). Some mail software
will prefix lines in message bodies with a `<code>&gt;</code>'
to avoid MUA's from incorrectly treating the line as a message
separator. However, some mail software doesn't.  </P>

<P>To avoid incorrect separator detection, many MUAs perform
a more stricter detection of separators beyond "<code>From </code>".
MHonArc, by default, will treat lines starting
with "<code>From </code>" as a message separator, which can lead to
incorrect message termination if the From line has not been escaped
with a `<code>&gt;</code>'.  </P>

<P>To fix the problem, use the
<a href="../resources/msgsep.html">MSGSEP</a> resource to
instruct MHonArc to use a stricter test detecting a message
separator. The following <a href="../resources/msgsep.html">MSGSEP</a>
resource setting is
known to work well: </P>

<pre class="code">
<b>&lt;MsgSep&gt;</b>
^From \S+\s+\S+\s+\S+\s+\d+\s+\d+:\d+:\d+\s+\d+
<b>&lt;/MsgSep&gt;</b>
</pre>

<p>In case you have message separates with quoted local parts in
the address part of the separator, you can use the following:
</p>

<pre class="code">
<b>&lt;MsgSep></b>
^From\s+(?:"[^"]+"<!--
-->&#64;<!--
-->\S+|\S+)\s+\S+\s+\S+\s+\d+\s+\d+:\d+:\d+\s+\d+
<b>&lt;/MsgSep></b>
</pre>

<p>Make sure to test things out before using in production
environments.
</p>

<p>If this fails, you can try the
<a href="../resources/conlen.html">CONLEN</a>
resource available in v2.0 and later.  The
<a href="../resources/conlen.html">CONLEN</a> resource, when set, tells
MHonArc to utilize the <code>Content-Length</code> fields
in the message head.  If your MTA defines this field accurately,
then you can utilize this feature.
Sun Solaris' delivery agent will define the
<tt>Content-Length</tt> field for messages delivered to local users.
</p>
<p>If you use Procmail to filter your mail,
you can try the following Procmail recipe (contributed by
<a href="mailto:lindsey&#37;40ncsa.uiuc.edu">Christopher Lindsey</a>):
</p>
<blockquote>
<p>However, one can add a Content-Length: header with everyone's favorite
tool, procmail.  :)  Here's a recipe borrowed from David Tamkin about
9 moons ago:
</p>
<pre class="code">
  :0fhw # B won't help; size conditions ignore H and B flags on the :0 line
  * ! ^Content-Length:.*[0-9]
  * 1^1 B ?? &gt;1
  | formail -a "Content-Length:  $="
</pre>
<p>So if you want to count on Content-Length, the message could be
piped into procmail with a specific procmailrc file which would 
do this counting and then call MHonArc.
</p>
</blockquote>

<p>If <a href="http://www.sendmail.org/">sendmail</a> is
your system's MTA and you use Procmail as your local delivery agent,
you can configure things to have <tt>Content-Length</tt> defined
for all locally delivered mail.  The following technique is
contributed by
<a href="mailto:tibbs&#37;40math.uh.edu">Jason L Tibbitts III</a>:
</p>
<blockquote>
<p>I use Procmail as my local delivery agent.  I have the following extremely
disgusting settings in my .mc (M4 config) file to add in a Content-Length:
header, <u>but I'm <b>not</b> sure if I would recommend that anyone
actually think of using this</u>:
</p>
<pre class="code">
define(`LOCAL_MAILER_FLAGS',`SPfhn9Z')
define(`LOCAL_MAILER_ARGS',`procmail -a $h -d $u')

LOCAL_CONFIG
#
# Add fake Content-Length Header for local mailer
# This is corrected by Procmail
# Note that the Z flag is used here; if Z is ever defined, this
#  will break something
H?Z?Content-Length: 0000000000
</pre>
</blockquote>

<p>If possible, try to avoid relying on the use of
<tt>Content-Length</tt> since it is hard to guarantee that it is
set properly.  When
<a href="../resources/conlen.html">CONLEN</a>
is specified, MHonArc will read at
least the number of bytes specified by <tt>Content-Length</tt> before
checking for the message separator, as defined by the
<a href="../resources/msgsep.html">MSGSEP</a>
resource.  Therefore, the value of <tt>Content-Length</tt> can be less
than the actual message size, and message extraction will
work as expected.  However, if <tt>Content-Length</tt> for a message
has a value that is larger than the actual size, MHonArc may include
the content of the next message as part of the current message.
</p>

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<hr noshade size=1>
<table border=0>
<tr valign=top><td><img src="monicon.png" align="bottom" alt=""></td><td>
<h3><b><a name="move">Can I move a message from one archive to another?</a></b></h3>
</td></tr></table>

<P>No. In order to achieve the same effect, you must add the original,
unprocessed, message to the destination archive, then remove the
appropriate HTML version of the message from the source archive.  </P>

<!-- ??????????????????????????????????????????????????????????????? -->
<hr noshade size=1>
<table border=0>
<tr valign=top><td><img src="monicon.png" align="bottom" alt=""></td><td>
<h3><b><a name="reconstruct">Can I reconstruct a database from the HTML messages?</a></b></h3>
</td></tr></table>

<p>Yes.  v2.3 of MHonArc introduced a utility program called
<b>mha-dbrecover</b>.  It gets installed with the other MHonArc
files during the installation process.  See the documentation for
usage information.
</p>


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<hr noshade size=1>
<table border=0>
<tr valign=top><td><img src="monicon.png" align="bottom" alt=""></td><td>
<h3><b><a name="dynamic">Is it safe to add messages to an archive as they are received?</a></b></h3>
</td></tr></table>

<p>Yes.  MHonArc performs archive locking to protect from
multiple MHonArc process attempting to write to an archive
at the same time.  This locking allows MHonArc to safely
be used to add messages as they are received.
</p>

<table class="note" width="100%">
<tr valign="baseline">
<td><strong>NOTE:</strong></td>
<td width="100%"><p>
As an archive increases in size, performing updates as
a message is received takes more processing time.  Therefore, for
large archives, you may need to do updates through a periodic
batch process (like via <b>cron</b>(8)) to avoid time-out problems
from MHonArc.
</p>
</td>
</tr>
</table>

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<hr noshade size=1>
<table border=0>
<tr valign=top><td><img src="monicon.png" align="bottom" alt=""></td><td>
<h3><b><a name="forward">So it is safe.  How do I do it??</a></b></h3>
</td></tr></table>

<p>Many users use <b>Procmail</b>
<a href="http://www.procmail.org/"
>&lt;http://www.procmail.org/&gt;</a> to call MHonArc
to archive messages.  Procmail provides the ability to preprocess
mail as it arrives to do selective processing and automated tasks
with your mail.
</p>

<p>For illustrative purposes, the following simple example shows
a possible way of archiving messages as it arrives w/o using a tool
like Procmail.
This example assumes you are on a Unix-based system
using <a href="http://www.sendmail.org/"><b>sendmail</b></a>
as the mail transfer agent.
Please refer to documentation about <b>sendmail</b> if you
are not familiar with it
(<cite><a href="http://www.ora.com/catalog/sendmail2/noframes.html"
>sendmail, 2ed</a>, from O'Reilly</cite> is an excellent source).
</p>

<p>The approach shown here uses a
<b><tt>.forward</tt></b> file in the home directory of the
account you want mailed archived.  For this example, let's
assume it is my account.
Here is how to set up the <tt>.forward</tt> file
to invoke MHonArc on incoming mail: </P>

<pre class="code">
\ehood, "|/home/ehood/bin/webnewmail #ehood"
</pre>

<table class="note" width="100%">
<tr valign="baseline">
<td><strong>NOTE:</strong></td>
<td width="100%"><p>
The "<code>\ehood</code>" tells <tt>sendmail</tt>
to still deposit the incoming message to my mail spool file. The
"<code>#ehood</code>" Bourne shell comment is needed to insure the
command is unique from another user. Otherwise, <tt>sendmail</tt>
may not invoke the program for you or the other user.
</p>
</td>
</tr>
</table>

<P><tt>webnewmail</tt> is a Perl program that calls
MHonArc with the appropriate arguments. A wrapper program
is used instead of calling MHonArc directly to keep
the <tt>.forward</tt> file simple, but you can call MHonArc
directly if you want. Here is the code to the
<tt>webnewmail</tt> program: </P>

<pre class="code">
#!/usr/local/bin/perl
# Edit above path to point to where perl is on your system.

##	Specify a package to protect names from MHonArc.

package WebNewMail;

##	Edit to point to installed mhonarc.

$MHonArc = "/home/ehood/bin/mhonarc";

##	Define ARGV (ARGV is same across all packages).
##	Edit options as required/desired.

<!--
-->&#64;<!--
-->ARGV = ("-add",
	 "-quiet",
	 "-outdir", "/home/ehood/public_html/newmail");

##	Just require mhonarc, this prevents the overhead of a
##	fork/exec.

require $MHonArc;

</pre>

<p>The <tt>webnewmail</tt> program has to have the executable
bit set.  This is achieved by using "<tt><b>chmod a+x webnewmail</b></tt>".
</p>

<table class="note" width="100%">
<tr valign="baseline">
<td><strong>NOTE:</strong></td>
<td width="100%"><p>
For better scalability and resource usage, the author
recommends calling MHonArc from a facility like <b><tt>cron</tt></b>,
which is provided on Unix-based operating systems.
For those unfamiliar cron, it is a daemon that allows the execution
of commands on scheduled basis.
</p>
</td>
</tr>
</table>

<!-- ??????????????????????????????????????????????????????????????? -->
<hr noshade size=1>
<table border=0>
<tr valign=top><td><img src="monicon.png" align="bottom" alt=""></td><td>
<h3><b><a name="majordomo">How can I do it with Majordomo lists?</a></b></h3>
</td></tr></table>

<p>Here is a
template for archiving messages as they arrive for a
Majordomo list to include in sendmail's <tt>aliases</tt> file:
</p>
<pre class="code">
<em>xxxx</em>:                "|<em>/usr/lib/majordomo/</em>wrapper resend -l <em>xxxx</em> <em>xxxx</em>-outgoing"
<em>xxxx</em>-outgoing:       :include:<em>/var/lib/majordomo/lists/</em><em>xxxx</em>, <em>xxxx</em>-mhonarc
<em>xxxx</em>-request:        <em>list-admin-address</em>
owner-<em>xxxx</em>:          <em>list-admin-address</em>
<em>xxxx</em>-owner:          <em>list-admin-address</em>

<em>xxxx</em>-mhonarc:        "|<em>/usr/lib/majordomo/</em>wrapper mhonarc -add -quiet -outdir <em>/home/httpd/html/yyyyyyy</em> <em>-rcfile rcs.mrc</em> <em>-stderr /var/log/mhonarc</em>" 
</pre>

<p>Replace text that <tt class="icode"><em>is rendered like this</em></tt> with
what is appropriate for your configuration.
</p>
<p>In order to run MHonArc with Majordomo's wrapper, the program has to 
be in the same directory where the Majordomo programs are located. 
An easy way to insure this is to create a symbolic link to in Majordomo's
program directory to where MHonArc is installed.  For example:
</p>
<pre class="shell">
prompt&gt; <b>ln -s <em>/usr/bin/mhonarc</em> <em>/usr/lib/majordomo/mhonarc</em></b>
</pre>
<p>Make sure <em><tt>/usr/bin/mhonarc</tt></em> is readable and executable
by the majordomo user.  Something like the following can be done
to insure this:
</p>
<pre class="shell">
prompt&gt; <b>chmod <em>755</em> <em>/usr/bin/mhonarc</em></b>
</pre>
<p>If you redirect stderr to a logfile, the logfile must 
be owned by the majordomo user and be writable by the majordomo user.
The directory for that logfile must exist.
</p>
<p>The MHonArc-archive directory must be owned by the majordomo user
and must have the minimum access permission 755.  Group ownership does not
matter.
</p>

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<hr noshade size=1>
<table border=0>
<tr valign=top><td><img src="monicon.png" align="bottom" alt=""></td><td>
<h3><b><a name="different">Can I get MHonArc to filter messages to different archives?</a></b></h3>
</td></tr></table>

<p>No.  This is outside of the MHonArc's scope.  You can grow your
own filter, using the method described in the
<a href="#forward">previous question</a>, to
scan the message header an invoke MHonArc with the proper arguments.
Or. you can use a tool like
<b>Procmail</b>
<a href="http://www.procmail.org/"
>&lt;http://www.procmail.org/&gt;</a>.
</p>

<table class="note" width="100%">
<tr valign="baseline">
<td><strong>NOTE:</strong></td>
<td width="100%"><p>You may want to check out the following:
<strong><a href="http://www.mhonarc.org/release/mharc/">mharc</a></strong>
at <a href="http://www.mhonarc.org/release/mharc/"
>&lt;http://www.mhonarc.org/release/mharc/&gt;</a>:
Mharc is a web-based mail archiving system for multiple mailing
lists using Procmail, MHonArc, and Namazu.
</p>
</td>
</tr>
</table>

<p>Here are a some messages from users about using Procmail:
</p>

<blockquote class="mail">
<UL>
<LI><em>From</em>: Achim Bohnet &lt;<A HREF="mailto:ach&#37;40rosat.mpe-garching.mpg.de">ach<!--
-->&#64;<!--
-->rosat.mpe-garching.mpg.de</A>&gt;</LI>
<LI><em>Date</em>: Wed, 13 Nov 1996 13:56:08 +0100</LI>
</UL>
<pre>
<var>... some text deleted ...</var>

Here is what I use in .procmailrc to archive the mhonarc list:

NEWDATE="`/usr/bin/date +%Y-%m`"
MHONARC_MBOX="/local/mail/lists/mhonarc/$NEWDATE.mbox"
:0: $MHONARC_MBOX$LOCKEXT
* ^Sender:.*owner-mhonarc<!--
-->&#64;<!--
-->
{
        :0 c
        $MHONARC_MBOX

        :0 c
        | /local/mail/mhonarc-1.2.2/mailarchive -add mhonarc "$NEWDATE"
}

Mailarchive is nothing more than a wrapper around mhonarc with my long.
list of options.

Achim
P.S. Procmail itself comes with an example manual page. It's worth
     looking into it.

</pre>
</blockquote>

<blockquote class="mail">
<UL>
<LI><em>From</em>: "Eric D. Friedman" &lt;<A HREF="mailto:friedman&#37;40hydra.acs.uci.edu">friedman<!--
-->&#64;<!--
-->hydra.acs.uci.edu</A>&gt;</LI>
<LI><em>Date</em>: Wed, 13 Nov 1996 06:38:42 -0800</LI>
</UL>
<pre>
You can actually dispense with the wrapper if you use environment
variables to pass options to MHonArc, but I'm sure Achim has a good
reason for doing it his way.  Just for the purposes of comparion,
here's how I do it:

eeeweb% cat .procmailrc
#Set on when debugging
VERBOSE=off
#Replace `mail' with your mail directory (Pine uses mail, Elm uses Mail)
MAILDIR=$HOME/Mail
#Directory for storing procmail log and rc files
PMDIR=$HOME/.procmail
#Path and options for mhonarc
MHONARC='/dcs/packages/infosys/bin/mhonarc -add -quiet -umask 022 -idxfname inde
x.html'
:0
* ^Originator:.*<!--
-->&#64;<!--
-->classes.uci.edu
{
  MHHOME=$HOME/classarc
  LOGFILE=$PMDIR/classlists.log
  INCLUDERC=$PMDIR/rc.classlists
}
:0 E
{
  MHHOME=$HOME/mail-arc
  LOGFILE=$PMDIR/otherlists.log
  INCLUDERC=$PMDIR/rc.otherlists
}

and then in the file .procmail/rc.classlists or rc.otherlists (depending
on the Originator: of the message), lots of the following:

# Procmail Entry for uci-www
:0 E
* ^TOuci-www
{
  :0 c
  uci-www/.

  :0
  |$MHONARC -rcfile $MHHOME/uci-www/0-rcfile.html -outdir $MHHOME/uci-www
}

Eric D. Friedman
friedman<!--
-->&#64;<!--
-->uci.edu
</pre>
</blockquote>

<blockquote class="mail">
<UL>
<LI><em>From</em>: Paul McKinley &lt;<A HREF="mailto:mckinley&#37;40austin.asc.slb.com">mckinley<!--
-->&#64;<!--
-->austin.asc.slb.com</A>&gt;</LI>
<LI><em>Date</em>: Mon, 21 Apr 1997 15:29:08 -0500</LI>
</UL>
<pre>
<var>... some text deleted ...</var>

I use procmail to drive mhonarc archives from Majordomo.  I set up a
single pseudouser and drive several archives from the one pseudouser. 

Here's a sample .forward file:

"|/usr/ucb/rsh cappuccino \"set IFS=' '; exec
/usr/local/procmail/bin/procmail #widget\""

Another example is:

"|/bin/csh -c \"set IFS=' '; exec /usr/local/procmail/bin/procmail
#widget\""

Two reasons to use the "rsh cappuccino":
1. doesn't require the user to be able to login to server, although
   the username must still be valid
2. gets the processing load off the mail server

Here's an example .procmail recipe:

LOGFILE=$HOME/procmail_errors
LOGABSTRACT=all
LOCKEXT=.lock
VERBOSE=on
UMASK=003

# widget: list short description
:0 H
* ^List-Name: widget
{
  # The rotate call (under construction) does archive rotation
  # leave commented!
  #:0c i
  #| /home/web-arch/bin/rotate /usr/local/web/webarchive/widget

  # Put the mail in the mailbox, which is used by archiver to re-generate
  # the html indexes
  :0 cA
  /usr/local/web/webarchive/widget/current/mbox

  # The mhonarc call examines mbox, turns the mail messages into .html
  # documents, and compiles the indexes.
  # -reverse -treverse\
  :0 ia
  | /usr/local/mhonarc/bin/mhonarc \
    -idxfname index.shtml \
    -tidxfname threads.shtml \
    -rcfile widget.rc\
    -outdir /usr/local/web/webarchive/widget/current \
    /usr/local/web/webarchive/widget/current/mbox

}

I have a directory per archive, and put the current period in directory
"current".  Then I have an index page per archive that indexes the
periods, plus gives information about the list and how to
subscribe/unsubscribe.  The widget.rc file resides in the pseudouser's
home directory.

Note the 
* ^List-Name: widget
I put the following in the majordomo list's config file:

message_headers   &lt;&lt;  END
List-Name: widget
END

This adds the "List-Name" header to messages, which is what procmail
filters for.

Hope this helps

Paul McKinley
Unix SysAdmin Contractor
</pre>
</blockquote>

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<hr noshade size=1>
<table border=0>
<tr valign=top><td><img src="monicon.png" align="bottom" alt=""></td><td>
<h3><b><a name="exclude">Does MHonArc support the "no archive" flag in messages?</a></b></h3>
</td></tr></table>

<p>Version 2.4, or later, does via the
<a href="../resources/checknoarchive.html">CHECKNOARCHIVE</a>
resource.
</p>

<p>If using an earlier version, or if you are already doing some preprocessing,
you can use a pre-processor like <b>Procmail</b>
to do the filtering.  Here is a message sent to the
<a href="mailto:mhonarc-users&#37;40mhonarc.org">MHonArc mailing list</a>:
</p>

<blockquote class="mail">
<UL>
<LI><em>Subject</em>: Re: No archive</LI>
<LI><em>From</em>: Christopher Lindsey &lt;<A HREF="mailto:lindsey&#37;40ncsa.uiuc.edu">lindsey<!--
-->&#64;<!--
-->ncsa.uiuc.edu</A>&gt;</LI>
<LI><em>Date</em>: Thu, 1 Oct 1998 11:33:07 -0500 (CDT)</LI>
</UL>
<pre>
&gt; Subscribers who don't want their messages to be archived
&gt; could add a "no archive" flag within their mail.

The most common way to do this is by checking for the existence
of an 'X-no-archive: yes' or 'Restrict: no-external-archive' header.

&gt; As I'm invoking MHonArc through a procmail recipe I guess
&gt; it's possible to do this within the recipe.

Very easy:

   # If people don't want to be archived, then remove their
   # message
   :0
   * ^(X-no-archive: yes|Restrict: no-external-archive)
   /dev/null

Chris
</pre>
</blockquote>

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<hr noshade size=1>
<table border=0>
<tr valign=top><td><img src="monicon.png" align="bottom" alt=""></td><td>
<h3><b><a name="addsafe">Is it safe to specify <tt>-add</tt> when no archive exists?</a></b></h3>
</td></tr></table>

<p>Yes.  If MHonArc sees no archive exists when perform
an add, it will automatically create the archive.
</p>

<table class="caution" width="100%">
<tr valign="baseline">
<td><strong style="color: red;">WARNING:</strong></td>
<td width="100%"><p>
If using MHonArc versions 2.4, or earlier, make sure the file
<tt>maillist.html</tt> (or the value
of the IDXFNAME resource) does not exist if no archive exists and
<tt>-add</tt> has been specified.  Otherwise, unpredictable output
of the <tt>maillist.html</tt> file may result if <tt>maillist.html</tt>
is not in the proper format.
</p>
</td>
</tr>
</table>

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<hr noshade size=1>
<table border=0>
<tr valign=top><td><img src="monicon.png" align="bottom" alt=""></td><td>
<h3><b><a name="jumps">Why are there "jumps" in message numbers?</a></b></h3>
</td></tr></table>

<p>Big gaps in the message number sequence may occur if you
defined the
<a href="../resources/maxsize.html">MAXSIZE</a>
resource and you have
MHonArc rescanning a mail folder for adding new messages.
The problem occurs when MHonArc
reads in messages that will automatically get deleted due
to
<a href="../resources/maxsize.html">MAXSIZE</a>.
Ie.  Messages subject to automatic deletion are
the oldest ones.  If the input contains old messages that will
get deleted at the end of processing, the old messages will
still use up message numbers since messages to be deleted are not
determined until all input is read.  Since MHonArc does
not keep information about deleted messages, if the messages are
fed into MHonArc again, the "jumping" will occur
again (and the jump will get larger for each additional update).
</p>

<p>To avoid the problem, try to pass only new, never processed,
messages to MHonArc instead of having MHonArc
rescanning the same mail folder for new messages.  Another
approach is to set either the
<a href="../resources/expireage.html">EXPIREAGE</a> or
<a href="../resources/expiredate.html">EXPIREDATE</a>
resources (available in v2.0 beta 2,
or later).  These work as an alternative to
<a href="../resources/maxsize.html">MAXSIZE</a>
and will help in
preventing message number jumping since expiration of a message is
checked when it is initially read (bypassing the assignment of
a message number).  </p>

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<hr noshade size=1>
<table border=0>
<tr valign=top><td><img src="monicon.png" align="bottom" alt=""></td><td>
<h3><b><a name="dups">Why do some messages get re-added each time MHonArc processes a mail folder?</a></b></h3>
</td></tr></table>

<p>This condition may occur when you have MHonArc examine the
same folder periodically to add any new message.  If there are
messages in the folder without message-ids, then those messages
will be re-added each time MHonArc runs.
</p>

<p>Why?  Well, MHonArc uses message-ids for determining if a
message has been archived, or not.  Therefore, if a message-id
is missing for a message, then MHonArc believes it is new.
</p>

<p>In general, mail has message-ids.  They get assigned by
MTAs.  However, if messages are generated by a CGI
program, or other non-mail specific software, then the program
in question should create a message-id.  Else, you will need
to move already-processed messages into a different area so
MHonArc does not read them again.
</p>

<table class="note" width="100%">
<tr valign="baseline">
<td><strong>NOTE:</strong></td>
<td width="100%"><p>
In MHonArc v2.4 and later, and if you have
the <b>Digest::MD5</b> module installed, MHonArc will compute
the MD5 digest of message headers without message-ids.  This
allows MHonArc to skip the message in subsequent add operations.
</p>
</td>
</tr>
</table>

<p>A related problem is messages showing up again in the archive
after you deleted them with RMM.  MHonArc does not keep track of
delete message-ids.  Therefore, if want to make sure that
a message will not appear in the archive after explicitly deleted
via RMM, make sure to remove the message from input source.
</p>

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<hr noshade size=1>
<table border=0>
<tr valign=top><td><img src="monicon.png" align="bottom" alt=""></td><td>
<h3><b><a name="remove">How do I remove messages from an archive?</a></b></h3>
</td></tr></table>

<p>Automatic removal can be done via the
<a href="../resources/expireage.html">EXPIREAGE</a> or
<a href="../resources/expiredate.html">EXPIREDATE</a>
resources (available in v2.0 beta 2,
or later) or the
<a href="../resources/maxsize.html">MAXSIZE</a>
resource.
</p>
<p>Explicit message removal can be done with the
<a href="../resources/rmm.html">RMM</a>
resource.  Please read the RMM resource page for more information
and examples.
</p>

<!-- ??????????????????????????????????????????????????????????????? -->
<hr noshade size=1>
<table border=0>
<tr valign=top><td><img src="monicon.png" align="bottom" alt=""></td><td>
<h3><b><a name="tombox">Can I convert an archive back to mailbox format?</a></b></h3>
</td></tr></table>

<p><a href="mailto:anthonyw&#37;40albany.net">Anthony W</a> provides a
Perl program called <tt>mhn2mbox</tt> for converting archives back
into mailbox format.  To obtain more information and to download
the program, goto
<a href="http://www.albany.net/~anthonyw/mhonarc/"
>&lt;http://www.albany.net/~anthonyw/mhonarc/&gt;</a>.
</p>

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$Date: 2003/10/06 22:04:15 $ <br>
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