Re: ProDOS filetype question

[Jim Pendarvis <jpendarv@patriot.net>]

Prodos itself only uses the hex digits. It is up to the system
program to further define them as it chooses. Some of these
(such as $04="TXT", $06="BIN", $1A="AWP") are pretty much standardized,
but even those might not be guaranteed. For example, $FF is
generally recognized as a Prodos 8 system file. Early versions
of Appleworks used $FF for its program overlays. They would
show up as system files in your program selector, but you
couldn't run them.

Other file types might or might not be defined at the whim of the
program. You have already discovered that with Shrinkit. Most programs
use the 2-digit hex codes for its undefined types, but they don't
have to. Appleworks not so helpfully uses "???" when it encounters what it
considers an undefined type (which is most of them).

For less common types you may find different programs call them something
different. If this bothers you, then you can often use a zap program
to change them within the offending program.

Keep in mind that whatever you see besides the 2-digit hex codes is
for your benefit, not Prodos. It will always use the hex codes. So
if you decide to change the type of the file itself, a program
that expects a certain value may not recognize it. This was a common
problem with fonts and Publish It! for a while.

AUXTYPES are a different matter. Different programs use them for different
things. Appleworks uses it as a mask for the lower case file name. GS
graphics uses it to identify subtypes of graphics. Binary files use
it as their load address. These are just a few examples.

Any list that claims to be a complete list of file types might or
not be correct for any given program.

jim

On Wed, 28 Feb 2001, Dennis Jenkins wrote:

> Hello all,
> 	ProDOS has some file types that show up as 2 hex digits and some that
> show up as three letter abbreviations.  Different prodos disks recognize
> different extensions.  I have found a list of all known extensions [1].
>
> 	ex: I have several different versions of ProDOS on floppy, and some
> recognize some files while others recognize a different set.  I have the
> 8 bit prodos that comes with GS/OS 6.0.1 (I assume that was the last
> official ProDOS...).  It does not recognize type $e0 (a shrinkit
> archive).  Yet when I boot from the shrinkit floppy, that prodos does.
>
> 	Does ProDOS distinguish file types using the AUXTYPE info as well?  $5a
> is not just for zlink config files, but for many different types of
> config files.  I assume that there is a (formal) way to patch ProDOS so
> that it will display the symbolic name for a new extension instead of
> just the hex digits (when doing a 'cat' for example).  Where can I get a
> copy of prodos that recognizes all extensions?  Or, how can I hack
> prodos to have all of the types that I use.  I assume that ProDOS would
> run out of space if it tried to store the abbreviation for ALL file
> types...
>
>
> 1) http://ground.ecn.uiowa.edu/apple2/Technotes/Ftn/FT.!INDEX
>
> --
> dennis@usb.com                           Universal Savings Bank.
>
> The three most dangerous things are a programmer with a soldering
> iron, a manager who codes, and a user who gets ideas.
>