[Pan-users] Re: Problem downloading multipart messages

[Duncan]

Edith Gross posted
<address@hidden>, excerpted below, 
on Sun, 18 Jan 2004 00:59:54 +0100:

> If I want to download a multi part message consisting of say 41 parts and 
> parts 8 and 10 are missing, but on another server the parts are there (but 
> in turn, other parts are present).
> 
> Can I download the message, that is, can I download the parts from 
> different servers?

Downloading isn't the problem.  That's easy.  Simply ensure that you have
turned any incomplete-part filters off, and d/l the parts from the
different servers.  Since PAN stores messages by msg-id in a common
directory cache, they are even in the same place (along with everything
else, of course).

The problem is getting PAN to combine them after they are downloaded, if
no server has all parts complete in their overviews (which can be quite
different than actually having the message bodies actually available,
particularly if you are on a buggy server).  Currently, there's no way to
get PAN to do it automatically, since PAN doesn't have "virtual servers"
yet, a feature that will be possible after the planned back-end database
switch to the sqlite libraries (making all sorts of fancy stuff possible,
tho it'd still need programmed).  Virtual servers would allow you to group
the views from multiple servers into one "virtual server" view, thus,
allowing you to assemble the parts from several different servers.

That doesn't mean it's IMPOSSIBLE to recombine them, after downloading
them with PAN.  It just means you have to do it manually, which unless you
develop a script to automate the process (tho you'd still have to
do it outside of PAN, unfortunately), means it's more work than is likely
to be worth it for most stuff.  Basically, you have to strip the headers
and text portions from each part, then cat parts*.msg>whole-encoded.msg,
then use a decoder to turn the combined encoded message back into a normal
binary.  There are such stand-alone decoders out there, and even scripts
to make stripping the text from the binary portions and combining the
parts easier as well, sometimes in combination with the decoders. 
However, particularly if you don't know anything about the internals of
news codecs, and/or scripting, it'd be a pretty big task, and could
be, even just finding a pre-made one, tho there are such scripts and
pre-build modules (as from perl) out there.

-- 
Duncan - List replies preferred.   No HTML msgs.
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