when images are not found

[Karl Berry]

(Switching to texinfo-devel for useless posterity.  Topic is what
happens when an image file cannot be found by makeinfo.)

    [for docbook] basefile.jpg is used if nothing is found.
    For HTML basefile.jpg is also used.  
    ...
    and there is no warning if no file is found.  

I don't think this is right.  TeX complains if it can't find the image.
Therefore I think makeinfo should too.

In C makeinfo, there was a warning with HTML output.  There was no
warning with Docbook output, which was simply an oversight.

So, I think Perl makeinfo should give a warning if it can't find the
image, and then yes, default to .jpg (that's what C makeinfo does).

Now, if we wanted to really support building manuals without access to
their images (the only reason for not giving a warning that I can see),
we could do that; it would imply a lot more work.  But no one is asking
for that, so I don't see any reason to go further.

    For XML no image file is searched for.

Ok :).

    In Info the alt is used if no file.txt is found, and, if there is no
    alt the bsefile itself is used as text without any extention.

Ok.  I see that's what C makeinfo does.  I think it should give a
warning if there is no .txt and no alt string.  (C makeinfo gives a
warning even if there is alt text, but that seems unnecessarily strict
to me now.)

Wdyt?

Thanks,
Karl