Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uwm.edu!ux1.cso.uiuc.edu!dino!ceres!zaphod.mps.ohio-state.edu!lavaca.uh.edu!jane!cosc10s4
From: cosc10s4@jane.uh.edu (A JETSON News User)
Newsgroups: comp.sys.mac.programmer
Subject: Re:Think C 4.0 questions
Message-ID: <5432.25c87f04@jane.uh.edu>
Date: 2 Feb 90 00:25:08 GMT
References: <10682@bsu-cs.bsu.edu>
Organization: University of Houston
Lines: 30

In article <10682@bsu-cs.bsu.edu>, mithomas@bsu-cs.bsu.edu (Michael Thomas Niehaus) writes:
> I have several questions that I hope someone out there can answer:
> 
> 1.  If you declare an array in an object class definition, is it safe to
>     use that array in a call to, say, an FSWrite routine?  I have created
>     a 1K buffer and when it fills up I want to call FSWrite to write the
>     whole chunk out.  Is this safe, or do I have to copy the whole array?
>     (Or can I lock it down?)

	As long as you are calling a routine, such as File Mgr calls, that
	don't move memory this is OK. If you are calling a routine, say
	EraseRect(), that can move memory, either HLock( this) temporarily
	or copy the instance variable to a local variable. 
> 2.  If you declare a superclass and then two or more subclasses, is it
>     possible to create an object of one subclass and assign it to an object
>     variable of the superclass?  I would like to have an array of objects of
>     different types (but of similar structures).

	Yes, you can do this.
> 3.  What does the debugger look like?  (My poor little 1MB SE has never seen
>     it.)
	It's very nice :-)

	Hopefully someone else can give a concise answer for your other
	two questions. 
--------------------------------
Dan Podwall
CS student, University of Houston
COSC10S4@jane.uh.edu
--------------------------------