Subj : Re: huge memory model
To   : borland.public.cpp.borlandcpp
From : "vYv" <vyv@sympatico.ca>
Date : Mon Apr 12 2004 11:27 am

Thanks for your prompt reply.  I found it quite informative.

As regards the huge global arrays, is there any way to keep the executable
size down without using malloc/farmalloc?  Ultimately I am writing a fully
standalone program (no calls to any operating system, I will rework the
startup files for my needs) and because it only requires a couple large
(>64k) arrays I was hoping to use intrinsic types rather than the normal
malloc functions (bad programming practice I know, but I'd rather not
write/find new malloc routines...perhaps it would be easier in the long run
though).

I am still in the researching phase of this hobby project.  Any info will be
much appreciated.

Cheers
vYv


"Ed Mulroy [TeamB]" <dont_email_me@bitbuc.ket> wrote in message
news:4079f8ad$1@newsgroups.borland.com...
> In large memory model the data segment in which global and static data
> is placed is one segment and the hardware limits a segment to 64K.
>
> In huge memory model the data segment in which global and static data
> is placed is still limited to 64K by the hardware.  However each
> source file has its own data segment so, independently of if it makes
> good programming sense, and it rarely if ever does, one can declare
> more than 64K of global and static data per program.
>
> Huge global arrays are not related to huge model.  They are about as
> easy to do in large or even small model as they are in huge.  Declare
> a pointer to the array globally and allocated it at runtime early in
> main with a call to farmalloc.
>
> For example:
>
>   ---------------------
>   #include <stdio.h>
>   #include <alloc.h>
>
>   char huge *big_array;
>
>   int main()
>       {
>       /* don't forget farmalloc takes an unsigned long */
>       big_array = farmalloc(256 * 1024UL);
>
>       if (big_array == NULL)
>           {
>           printf("Not enough memory to run the program\n");
>           return 1;
>           }
>
>       ----normal program code here---
>       farfree(big_array);
>       return 0;
>       }
>   ---------------------
>
> .  Ed
>

.