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Re: 8-bit unzip utility



mdj wrote:
On Jun 21, 7:02 pm, "Michael J. Mahon" <mjma...@aol.com> wrote:


I have several times had a need to pass a small integer to a program
and thought it would be most convenient to pass it on the command line
that invoked the program.

ProDOS parses, converts, and ignores the "V" (volume) specifier after a
program name (which is interesting, since it should probably give a
syntax error).

This opens the possibility of passing a single-byte value, since values
of 0-255 are acceptable.

Unfortunately, ProDOS discards the value after converting it to binary,
so the program will have to re-scan the "V" parameter out of the input
buffer ($200) and re-convert it, but at least it's possible.


Huh! Well I never knew that. Thanks Michael, that's handy to know.

Curious why they decided to implement some 'dummy' command arguments
for DOS 3.3 compatibility but left others out; MAXFILES for instance.

I'm not sure this was left in for compatibility--probably just the left
hand not having the same objectives as the right hand.  ;-)

I wish that they had stuffed the converted value into the BASIC.SYSTEM
global page byte reserved (uselessly) for the Volume, though.  They
saved one STA and cost a re-scan for someone who wants to exploit it.
(This might be a good patch, now that BASIC.SYSTEM isn't likely to
change any more. ;-)

-michael

NadaNet file server for Apple II computers!
Home page:  http://members.aol.com/MJMahon/

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