Re: Y2K ProDOS 8 (2.0.3)

["Charlie" <charlied@NOSPAMbboard.com>]

"Michael J. Mahon" <mjmahon@aol.com> wrote in message
20030712212553.14728.00000298@mb-m07.aol.com">news:20030712212553.14728.00000298@mb-m07.aol.com...
> Charlie wrote:
>
> >At the time that ProDOS was written most software on the Apple II ran under
> >DOS
> >3.3 which has no support for date and time stamping.  It is possible that
> >programs that ran under other systems (Apple III SOS, CP/M, Pascal, etc.)
may
> >have had a similarly bit challenged date system (I don't know enough about
> >those systems to argue the point) but from what I've seen of Apple (the
> >company) over the years, compatibility isn't high on their list of
> >priorities.
>
> Whatever the reasons for the original design choices (like trying to keep
> date and time as independent 16-bit fields) or the consequences for
> post-1999 systems, the fact remains that this date format was made
> an externally visible interface for ProDOS, and so cannot be changed
> now without either:  1) changing all applications that use the date
> structure (a very unappealing choice),

Agreed.  Breaking existing programs is rarely a good idea.  My reason for
pointing out the unused bits was not to suggest that they now be used but only
that when ProDOS was initially conceived there was room for more years.

> or 2) adding a _new_ date
> interface to ProDOS which preserves some kind (Apple's kind?)
> of compatibility for unchanged applications and adds a new date
> interface for applications which can be changed to take advantage
> of it.

One way would be to just keep the _new_ dates in an indexed file.  A program or
a new (patched) version of ProDOS could look up the date in the file.  If not
found it would fall back on the old way.

> Although the second alternative is appealing, it has the problem
> that it is unlikely that many applications would actually exploit
> it in the coming years.

True.

> I'm also unsure of how much free space is available for ProDOS
> changes these days...

This may be the show-stopper.

Charlie