[comp.sys.apple] resource forks vs. data forks

TMPLee@DOCKMASTER.NCSC.MIL (05/11/89)

Not being one who has ever had any intimate acquaintances with
MacIntoshes, could someone explain the new (to the GS) concept of
resource forks, and, in particular how they fit into teh ProDos file
structure?  There are a lot of old (P8-based) utilities that work just
fine on P16 and GS/OS files since the file system hasn't changed, just
the operating system.  Will that continue to be true in the brave new
world?  (I note as it is that the format of directories seems just
slightly different between GS/OS and my old Beneath ProDos book, but
maybe the differences aren't important.)

TMPLee@Dockmaster.ncsc.mil

mattd@Apple.COM (Matt Deatherage) (05/11/89)

[In response to questions about resource forks]

GS/OS allows for files to have both data forks and "resource forks".  In the
most basic explanation, it's a way to link two separate files together
logically with one file name.  The resource fork is used by the Resource
Manager to hold resources (new for 5.0), and the data fork is the normal
part of the file we've always known.  You can think of a regular file as
an "extended" (two-forked) file with an empty resource fork.

Actually, you can't quite do that physically.  Those familiar with ProDOS know
that the file system did not originally include any definitions for two-forked
files, so one was created for the ProDOS FST under GS/OS.  It uses ProDOS
storage type 5.  Because of this, ProDOS 8 applications can not work with
extended files.

This brief yet muddled overview can be supplanted by much better informatino
in "GS/OS Reference, Volume 1".


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mdavis@pro-sol.cts.com (Morgan Davis) (05/16/89)

Network Comment: to #7091 by pnet01!crash!apple.com!mattd

Matt,

Will the GS/OS 5.0 loader be smart enough to load CODE resources from an
application's resource fork, or is it always assumed that the loader
information and executable code will be stored in the data fork?

--Morgan Davis

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dlyons@Apple.COM (David Lyons) (05/18/89)

In article <8905161918.AA00826@crash.cts.com> pnet01!pro-sol!mdavis@nosc.mil writes:
>Network Comment: to #7091 by pnet01!crash!apple.com!mattd
>
>Matt,
>
>Will the GS/OS 5.0 loader be smart enough to load CODE resources from an
>application's resource fork, or is it always assumed that the loader
>information and executable code will be stored in the data fork?
>
>--Morgan Davis

Yes, there's a mechanism for automatically running resources through the
Loader.  It's pretty slick, and the system uses it for some things (meaning
that it's been tested :-).


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