[plt-scheme] new version of prog langs text (also making the collection work on r301.5 from svn)

From: Eli Barzilay (eli at barzilay.org)
Date: Tue Feb 7 18:49:44 EST 2006

On Feb  7, Geoffrey Knauth wrote:
> Eli's solution (application/plt-package) worked perfectly on my Mac.
> That is, the file was saved .plt and not .plt.txt.
> The fact that it had the right PLT icon, though, required a one-time  
> change telling Mac OS X that PLT owns .plt files, and not  
> GraphicConverter.  The "other" .plt is AutoCAD plot-to-file.

And Robby Findler wrote:
> Safari downloads it and saves it to the desktop. clicking on it opens a
> graphics program that then complains about it not actually being a
> graphics file.

That's an OS issue -- the same will happen on Windows if some other
app grabs the .plt extension.

On Feb  7, Greg Woodhouse wrote:
> The theory behind media (MIME) types is that they should be used to
> identify the resource type, not the file extension. So, in
> principle, if you have a URL like
> http://wherever.org/some-html.txt
> and some-html.txt is actually, HTML, then if the media type in the
> HTTP header is text/html, then the client (browser) knows that it is
> HTML and presents it accordingly.

Right -- but I think that what happened is that most browsers just
choose to ignore the mime type if it's generic enough and the OS has
an association for the the suffix.  Some browsers will be even more
annoying and decide to append some suffix for you (I think that I did
end up having some ...tgz.txt files a few times).

> I've never run into the problem you describe with .plt files, and it
> may be that I never installed the CAD application, but I would
> expect that metadata associated with the file would indicate that
> it's not an image.

-- If the OS has some place to save such meta data.  I actually
expected OSX to do this in a cleaner way than simply relying on the
file name.

> I had thought a generic media type like application/octet-stream
> would be nice because it would at least allow downloading the file
> with a single click. In fact, that's the behavior I expected, not
> having the installer launch automatically. (This was under Windows,
> but even on my PowerBook, clicking on the .plt files automatically
> launches the installer.)

That's a brower issue, no?  You should be given some right-click menu
entry for just saving the file (or have it ask what you want to do
when you click).

On Feb  7, Geoffrey Knauth wrote:
> This reminds me, even if the PLT Installer is changed to "take over"
> the .plt extension, the next time a Mac user installs an app like
> GraphicConverter, .plt will switch back again.

No solution for that, besides choosing some other extension...

          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
                  http://www.barzilay.org/                 Maze is Life!

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