Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!pacific.mps.ohio-state.edu!linac!midway!quads.uchicago.edu!jcav From: jcav@quads.uchicago.edu (john cavallino) Newsgroups: comp.sys.amiga.advocacy Subject: Re: STACK ON MAC VS AMIGA Message-ID: <1991Jun24.194314.3657@midway.uchicago.edu> Date: 24 Jun 91 19:43:14 GMT References: Sender: news@midway.uchicago.edu (NewsMistress) Organization: University of Chicago Lines: 38 In article NJ_GOKEMEIJE@FANDM.BITNET writes: >>From: IN%"dant@ryptyde.cts.com" 24-JUN-1991 13:12:49.37 >> >>"Yes, also a STACK on the mac can only be upto 32K" >> >>A stack can only be up to 32K? Stack of what? The data structure in >>general? What is the Amiga limit? > >on the Macintosh the stack for each program: the structure in general >can only be 32 K. >On the Amiga, the stack can be anysize I believe: at least up to 100 K >(matlab wants that) >Any bigger on the MAC and it will run it the system heap. You are incorrect. A Mac application defaults to a certain min. stack size (between 8 and 16K, depending on the machine model) but it can allocate more space at startup if it likes. In fact, it can give itself over 90% of it's memory space as stack if it wants. The stack allocation is done by resetting the application heap limit, which is the maximum space available for dynamic allocation. Less application heap --> more stack space, and vice-versa. >question: I believe every application has its own systemheap right? >But there is a bigsystemheap which can be accessed using TempNewHandle() >but in no other way right? Your belief is incorrect. There is one System Heap, which is where private OS structures and other shared items are allocated. The space from which temporary memory is allocated belongs to the Process Manager (used to be Multifinder), and has nothing to do with the System Heap. -- John Cavallino | EMail: jcav@midway.uchicago.edu University of Chicago Hospitals | USMail: 5841 S. Maryland Ave, Box 145 Office of Facilities Management | Chicago, IL 60637 B0 f++ c+ g+ k s+(+) e+ h- pv (qv) | Telephone: 312-702-6900