Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!purdue!decwrl!sun-barr!apple!dlyons
From: dlyons@Apple.COM (David Lyons)
Newsgroups: comp.sys.apple
Subject: Re: resource forks, encore une fois
Message-ID: <30956@apple.Apple.COM>
Date: 17 May 89 20:38:53 GMT
References: <890517140423.546278@DOCKMASTER.ARPA>
Organization: Apple Computer Inc, Cupertino, CA
Lines: 51

In article <890517140423.546278@DOCKMASTER.ARPA> TMPLee@DOCKMASTER.NCSC.MIL writes:
>I'm still troubled by the compatibility problem of introducing resource
>forks into ProDos.  (for one thing, all the statments made in the past
>about the ProDos8, ProDos16, and GS/OS file systems being identical are
>no longer true.)  someone's note about changing ECP16 to at least
>recognize the critters prompts me to ask a few questions ...

It's better to have resource forks that P8 can't read than not to have resource
forks at all.

Since ECP16 runs under GS/OS, it has no trouble dealing with extended files (an
"extended" file is one with 2 forks).

ProDOS 8 programs that want to deal with either fork of an extended file have to
do block-level access to the disk; this isn't recommended.

>1.  What happens when you are in old Basic.System and do a cat or
>catalogue command?  What will it show for a file that has a resource
>fork (i.e., storage type 5, I think someone said it was.)?

You can't tell from the BASIC.SYSTEM catalog which files are extended files
and which are standard files.  You can RENAME, LOCK, and UNLOCK the things,
but you can't DELETE them or do anything that opens the file (even the data
fork).  Extended files on ProDOS disks do indeed have storage type 5.

>2.  When System Disk 5.0 comes out, exactly which files on it will in
>fact be files with resource forks?

Don't know exactly.  All of the files in the system:CDEVs directory will be
extended.  The system:sys.resources file will obviously be extended.  There
are probably others.

>Does anyone know of any applications
>from third party vendors that will either use, be able to use,
>recognize, or otherwise properly handle forked files?

Anything running under GS/OS will be able to deal with the data forks of
extended files, even if the application was not specially written to know
about extended files.  Just asking to OPEN a file under GS/OS (on System
Disk 4.0 or 5.0) gets you the data fork by default.

>TMPLee@dockmaster.ncsc.mil

 --Dave Lyons, Apple Computer, Inc.          |   DAL Systems
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