MIME attachment not shown

MIME attachment not shown

[Tom Koelman]

Hi,

I have some emails which contain attachments I am not able to "see",
using Oort 0.05. I know the data is there (C-u g shows me all kinds of
mime-stuff plus my previous email program, Pegasus, is able to show
it), but Gnus just displays, well, nothing. The text accompanying the
attachment is there. Other emails containing attachments seem to
behandled correctly by Oort.

I guess that these mails don't conform to mime-standards or something
like that, and that that is why Gnus doesn't display them. How do I
determine what's wrong? What kind of headers should be there or could
I inspect?

Tom

-- 
The question seldom addressed is *where* Medusa had snakes. Underarm hair
is an even more embarassing problem when it keeps biting the top of the
deodorant bottle.  -- (Terry Pratchett, Soul Music)

Re: MIME attachment not shown

[Karl Kleinpaste]

Start with...
(setq gnus-unbuttonized-mime-types nil)
...and then finding out what clickable buttons result.

Re: MIME attachment not shown

[Tom Koelman]

Karl Kleinpaste wrote:

> Start with...
> (setq gnus-unbuttonized-mime-types nil)
> ...and then finding out what clickable buttons result.

it results in an extra line in front of the plain text:

1.  (*) text/plain          ( ) text/html           

which wasn't there without gnus-unbuttonized-mime-types set to nil. I
started to inspect the raw text of the mail and discoverd the
following.

In the header I see

Content-Type: multipart/related;
	type="multipart/alternative";
	boundary="----=_NextPart_000_0013_01BF4892.DC4815C0"

which I guess means that the multipart/alternative bit can be
extracted from the message by splitting on the lines containing
----=_NextPart_000_0013_01BF4892.DC4815C0

This line is in the message three times, which I think would split
this mime-part in two. Looking at the message, the second part would
be the image I am after, the first part is a multipart in itself,
which I conclude from the "NextPart" splitter in the actual message:

------=_NextPart_000_0013_01BF4892.DC4815C0
Content-Type: multipart/alternative;
	boundary="----=_NextPart_001_0014_01BF4892.DC4815C0"

This "NextPart...14" splitter is there three times, thereby splitting
the first mimepart in the message into two: a plain text and a html
version of the same text.

So, my guess is that Gnus correctly detects the first mime-part, and
after detecting that it can choose whether to display the HTML or the
plain text. Due to my preferences it displays the plain text and
normally just ignores the HTML, which is correct.
The second mime-part however, containing the image is skipped al
together. Is this a bug in the message, in Gnus or am I talking
complete gibberish?

Thanks, Tom

Re: MIME attachment not shown

[Karl Kleinpaste]

Tom Koelman <tkoelman@xs4all.nl> writes:
> it results in an extra line in front of the plain text:
> 1.  (*) text/plain          ( ) text/html           
> which wasn't there without gnus-unbuttonized-mime-types set to nil.

Right, that lets you see what the MIME analysis discovered.

> So, my guess is that Gnus correctly detects the first mime-part, and
> after detecting that it can choose whether to display the HTML or the
> plain text. Due to my preferences it displays the plain text and
> normally just ignores the HTML, which is correct.

So far, so good.

> The second mime-part however, containing the image is skipped al
> together. Is this a bug in the message, in Gnus or am I talking
> complete gibberish?

Well, you're halfway to gibberish, I'm afraid.  You evidently told
Gnus explicitly not to display text/html, something that a lot of us
do.  Having told Gnus that, it did what you wanted, ignoring the
component of that flavor.  Inline images are generally only
displayable as a function of HTML processing (other than for images
just plain inserted in their own right, as entire and independent
MIME components)

It is for this reason that I have gnus-unbuttonized-mime-types set to
nil all the time, so I am at least informed that Gnus made a choice on
my behalf, in accordance with my wishes.  If you want to see the
image, you'll have to toggle the text/html side of the posting, which
you can do with `b' (which takes as argument the part number to be
displayed, and part 1 is of course the default).

If you still don't see the image, you might experiment with whether 
(setq gnus-mime-display-multipart-related-as-mixed t)
helps you out.  This is a bug workaround due to problems in the past
of "related" components not being dealt with properly -- it makes
images intended as inline (especially background images) be displayed
after the intended component entirely, as though they were just
another of a "mixed" set.

Re: MIME attachment not shown

[Tom Koelman]

Karl Kleinpaste wrote:

> Well, you're halfway to gibberish, I'm afraid.  You evidently told
> Gnus explicitly not to display text/html, something that a lot of us
> do.  Having told Gnus that, it did what you wanted, ignoring the
> component of that flavor.  Inline images are generally only
> displayable as a function of HTML processing (other than for images
> just plain inserted in their own right, as entire and independent
> MIME components)

I see. The image indeed was referenced in the html part by some kind
of id, so I understand what's happening here now. The HTML somewhere
contains <IMG src="cid:000b01bf488a$7a15d0c0$0201a8c0@oemcomputer">
and the image has a remarkable similar line, namely: 
Content-ID: <000b01bf488a$7a15d0c0$0201a8c0@oemcomputer>

> If you want to see the image, you'll have to toggle the text/html
> side of the posting, which you can do with `b'. 

Which worked (it saved the html-part), except that it didn't do
anything with the related image, I assume because I haven't installed
w3 or something similar so Gnus can't parse the html.

> If you still don't see the image, you might experiment with whether 
> (setq gnus-mime-display-multipart-related-as-mixed t)
> helps you out.

Which worked! The image now indeed shows up and I am able to save it
like I wanted. Even better: I think I understand what I'm doing.
Thank you very much.

Tom

-- 
Om began to feel the acute depression that steals over every realist
in the presence of an optimist.  -- (Terry Pratchett, Small Gods)

Re: MIME attachment not shown

[Daniel Pittman]

On Sat, 02 Feb 2002, Tom Koelman wrote:
> Karl Kleinpaste wrote:

[...]

>> If you still don't see the image, you might experiment with whether 
>> (setq gnus-mime-display-multipart-related-as-mixed t)
>> helps you out.
> 
> Which worked! The image now indeed shows up and I am able to save it
> like I wanted. Even better: I think I understand what I'm doing.
> Thank you very much.

Alternately, you can usually use 'C-d' to view all the parts of the
message. I tend to do that, look at the image, then deal with it as I
desire.

        Daniel

-- 
With sufficient thrust, pigs fly just fine. However, this is not necessarily a
good idea. It is hard to be sure where they are going to land, and it could be
dangerous sitting under them as they fly overhead.
        -- RFC 1925