[Coco] Re: Multivue Disk side A

[Robert Gault]

tim lindner wrote:
> This disk has a demo directory:
> 
>                            Directory of mva.dsk,./DEMO
>  Owner    Last modified    Attributes Sector Bytecount Name
> -------   ---------------  ---------- ------ --------- ----
>   0.0     1987/08/02 2358   ----r-wr     26C        36 aif.dmo
>   0.0     1987/04/27 2252   ----r-wr     26E         0 lines.dmo
>   0.0     1987/04/27 2252   ----r-wr     26F         0 circles.dmo
>   0.0     1987/04/27 2252   ----r-wr     270         0 bars.dmo
> 
> The lines, circles, and bars demos have zero file size.
> 
> Is my disk bad? Or am I missing something?
> 

I'm glad you asked this question because it has forced me to relearn 
info on MultiVue.

Actually the 0 byte files are normal! If you start MV and click on them, 
a program will start running. So how can a 0 byte file do anything?!

MultiVue's gshell makes the above work. When the Demo directory is 
opened, gshell sees aif.dmo, lines.dmo, circles.dmo, and bars.dmo. If 
you click on lines.dmo, gshell sees that the "file" is neither a folder 
nor and executable so it "must" be a data file. There are two types of 
data files, aif.xxx or name.xxx. If the file is of the type name.xxx, 
then the corresponding aif.xxx file is opened and the indicated program 
is started. In this case, the program demo checks to see what started 
it. If it finds that a name.xxx data file called it, then the specific 
portion of the program is run. So if gshell uses lines.dmo to start the 
program demo (as indicated by aif.dmo) then the lines graphic starts 
running.

This demo is cute in that if started by a name.dmo file, the window in 
which the program runs has its size set by the user. If the program is 
started with the aif.dmo file, the window is full screen.