Re: What does NSAutoreleasePool actually do?

[黃俊傑(Chun-Chieh Huang)]

Willem Rein Oudshoorn <woudshoo@xs4all.nl> writes:

> "黃俊傑(Chun-Chieh Huang)" <jjhuang@cm.nctu.edu.tw> writes:
[stuff deleted]
> Because in dread.m the first line in the main method creates the 
> autorelease pool:
> 
>  ...
>   int
>   main(int argc, char** argv)
>   {
>       NSAutoreleasePool       *pool = [NSAutoreleasePool new];
>       NSUserDefaults  *defs;
>  ...

Yes, I saw it before I post. Actually, I misunderstood the OpenStep
specification written in 1994. The manual said that NSAutoreleasePool
will be automatically handled in NSApplication, but I thought
NSAutoreleasePool is only concerned with NSApplication. I forgot that
many Foundation classes, such as NSArray, will be autoreleased. Sorry
I didn't express myself clear. And I know that NSAutoreleasePool is
used by many Foundation classes, not only ApplicationKit. 

> > 
> > In my main.m, I created an NSAutoreleasePool, and create my simulator
> > instance, set it up, and then make it peform some actions. Finally, I
> > release my simulator instance and the pool.
> 
> This is the way most tools work.   
> Additionally you might want to create and destroy additional release pools
> in strategic places to avoid keeping objects alive till the tool exits.
> This is especially important for tools that are supposed to run for
> a long time.

Thanks for your suggestion. I'm working on it. Mini-tutorials from
Nicola Pero is a good starting point. I learned how to create nested
autorelease pools in these tutorials. I knew how to write programs in
OPENSTEP before, but I began to learn how it really works after porting
to GNUstep. :-)

> > I need to modify some
> > memory management, but it works. 
> 
> Hm, what do you mean with this.  Change where and why?  
> Probably perfectly alright but I am just puzzled.

Hm, sorry I didn't make myself clear. I mean I have to modify some
memory management method in my program. I knew little about memory
management in Objective-C until recently. I have to carefully examine
every step of memory alloc/release in my program, which was written on
OPENSTEP. Compared to C++/Java, there are really few resources for
Objective-C. I'm glad that I can continue to use Objective-C since
GNUstep was created. Maybe in the future, we can write applications once,
and execute the GNUstep application on UNIX/Win32/MacOS X, stably.

Best Regards,
Chun-Chieh

-- 
Chun-Chieh Huang(黃俊傑), or Albert | E-mail: jjhuang AT cm.nctu.edu.tw
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