Re: More Sparse Files.

[dlyons@Apple.COM (David A Lyons)]

In article <1992Nov20.043714.28585@fawlty.towers.oz.au> johnmac@fawlty.towers.oz.au (John MacLean) writes:
>[...]
>1) I need an existing commonly available commercial program that runs on
>a //e (such as Copy II Plus), that can create a disk image on a hard disk
>(or 3.5" disk) of a 5.25" disk.

There's something on the Apple CDs called "5.25 disk holder"...the title
screen reads:
                   ProDOS Packer 6.0 By R.Banning
                      Enhanced By Morgan Davis

I don't know whether it is commercial, public domain, or somehwere in
between, or by what arrangement it is on the CDs.  It runs under
BASIC.System.

>3) Is there a way, to force GS/OS with the ProDOS FST ONLY, to create
>files as non-sparse, even though the file contains large areas of zero
>bytes? - and if so how?

I think there's *one* way:  On the CreateGS call, provide values in the
eof and/or resource_eof fields.  This amount of space will be pre-allocated
during the create, even though it is initially all zeroes.  I don't know
whether you have to avoid rewriting zeroes to keep the non-sparseness.

(If you copy the file to a ProDOS disk using GS/OS, it will of course
become sparse.)

-- 
David A. Lyons, Apple Computer, Inc.      |   DAL Systems
Apple II System Software Engineer         |   P.O. Box 875
Internet:dlyons@apple.com                 |   Cupertino, CA 95015-0875

My opinions are my own, not Apple's.