Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!samsung!umich!ox.com!heifetz!tbomb!time
From: time@ice.com (Tim Endres)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Yikes: Using both resource & data forks of a file
Message-ID: <0B01FFFF.dbbnhif@tbomb.ice.com>
Date: 17 Apr 91 02:30:32 GMT
Reply-To: time@ice.com
Organization: ICE Engineering, Inc.
Lines: 24
X-Mailer: uAccess - Mac Release: 1.1.b1


In article <280B842C.16551@orion.oac.uci.edu>, bdugan@teri.bio.uci.edu (Bill Dugan) writes:
> I'm creating a document file with "Create", writing data to the file's
> data fork, and closing the file.  Everything's great.  But then I 
> want to put some resources in the file.  I am trying "OpenRFPerm" with
> write permission enabled, and it doesn't work; calling ResError() reveals
> an EOF, which leads me to believe there's no resource fork, despite
> IM's claim that Create will set up both forks of the file created.

IM is correct, but misleading. When you use Creat(), you are indeed
creating the *catalog* entries for both forks of the file. In fact,
I have verified this looking at the catalog for a new file. HOWEVER,
since the resource fork is initially empty, there is not even a resource
map for OpenRFPerm() to load, thus the EOF error. You must, therefore,
create the map (and other needed space) in the resource fork with
a CreateResFile() call. This is *certainly* not obvious from IM.

tim.

-------------------------------------------------------------
Tim Endres                |  time@ice.com
ICE Engineering           |  uupsi!ice.com!time
8840 Main Street          |  Voice            FAX
Whitmore Lake MI. 48189   |  (313) 449 8288   (313) 449 9208