Re: mm view PDF MIME part doesn't work, just exits

[Ted Zlatanov <tzz@lifelogs.com>]

On Sat, 29 Aug 2009 10:46:18 -0700 Mike Kupfer <m.kupfer@acm.org> wrote: 

>>>>>> "Ted" == Ted Zlatanov <tzz@lifelogs.com> writes:
Ted> I see "Displaying xpdf /tmp/emm.../file.pdf...done" and that's it.
Ted> xpdf doesn't come up as it should.

Ted> I customized the mailcap and mailcap-mime-data to ensure the right
Ted> thing is called, but no luck.  What should I do to debug this?

MK> The first thing I'd try is saving the attachment to a file, and then
MK> starting xpdf from a shell to view it.

That's what I've been using as a workaround.  The file is OK.

MK> If that works, I'd create a wrapper script and use it instead of the
MK> system xpdf.  For example, something like

MK>   echo $* > $HOME/xpdf.args
MK>   /usr/bin/xpdf $*

MK> could verify that the command-line arguments are correct.

That does not work.

MK> I recall seeing a thread not too long ago about problems that happen if
MK> a viewer daemonizes itself.  The parent (Emacs in this case) thinks that
MK> the viewer has finished, so it deletes the temp file, before the viewer
MK> has actually read in the temp file.  I'd be surprised if xpdf were doing
MK> that, but I suppose it's something you could check.

I debugged this down to mm-decode.el:mm-display-external which is a
pretty complicated process invoker.  The process sentinel gets process
status 'exit as soon as the process starts, and the `state' variable
says:

Displaying xpdf /tmp/emm.32715eef/KR090831.pdf...done (exited abnormally with code 1
)

(I changed the notification message to also display the state).

From the command line, all this works, e.g.:

zsh -c 'xpdf /tmp/emm.32715eef/KR090831.pdf'

which xpdf => /usr/bin/xpdf

Changing to explicitly launch /usr/bin/xpdf didn't make a difference, as
expected (/usr/bin is in PATH no matter what).

I'm really puzzled at this point.  I've CC-ed the people who have
touched mm-decode.el recently, hoping they can enlighten me.  FWIW this
used to work and I'm sure I haven't changed any settings that may have
changed its behavior.  This affects both RET and `e' on an external MIME
part so I'm surprised no one else has noticed it.

Ted