[fpc-pascal]Pointer Help
James Mills
prologic at prologitech.com
Sun Feb 9 13:50:05 CET 2003
On Sun, Feb 09, 2003 at 03:42:29PM +0100, Anton Tichawa wrote:
> Hi,
>
> > But getMem and reAllocMem allocate a number of bytes on the heap,
> > wouldn't you have to free that number of bytes using freeMem(pointer, n)
> > ?
>
> No, Free Pascal keeps track of the allocated size for a pointer created with
> GetMem/ReallocMem. They need this information for heap management, so it's a
> good think to use this information to save one procedure parameter, which is
> a lot. If you want to determine the number of bytes to deallocate, you may do
> this by using:
>
> Function FreeMemSize(var p:pointer;Size:Longint):Longint;
>
> Definition:
> FreememSize
> This function should release the memory pointed to by P. The argument Size is
> the expected size of the memory block pointed to by P. This should be
> disregarded, but can be used to check the behaviour of the program.
>
> I think with FreeMemSize you may corrput the heap, so be careful with it!
>
> Anton.
Ok thank you very muchly :) You've been a great help.
>
>
> >
> > Btw, I'm using short strings, so I think it'll be ok for now...
> >
> > > Read the Manual - Free Pascal Programmer's Manual, Section 4.5, "Writing
> > > Your Own Memory Manager" - because that's what you're actually doing.
> > >
> > > HTH
> > >
> > > Anton Tichawa.
> > >
> > >
> > >
> > > ----------
> > >
> > > "Adas Methode war, wie sich zeigen wird, Tagtr?ume in offenbar korrekte
> > > Berechnungen einzuweben."
> > >
> > > Doris Langley Moore: Ada, Countess of Lovelace (London 1977).
> > >
> > > ----------
> > >
> > > Anton Tichawa
> > > Volkertstrasse 19 / 20
> > > A-1020 Wien
> > > mobil: +43 664 52 07 907
> > > email: anton.tichawa at chello.at
> > >
> > > ----------
> > > _______________________________________________
> > > fpc-pascal maillist - fpc-pascal at lists.freepascal.org
> > > http://lists.freepascal.org/mailman/listinfo/fpc-pascal
> >
> > _______________________________________________
> > fpc-pascal maillist - fpc-pascal at lists.freepascal.org
> > http://lists.freepascal.org/mailman/listinfo/fpc-pascal
>
> --
>
> ----------
>
> "Adas Methode war, wie sich zeigen wird, Tagtr?ume in offenbar korrekte
> Berechnungen einzuweben."
>
> Doris Langley Moore: Ada, Countess of Lovelace (London 1977).
>
> ----------
>
> Anton Tichawa
> Volkertstrasse 19 / 20
> A-1020 Wien
> mobil: +43 664 52 07 907
> email: anton.tichawa at chello.at
>
> ----------
> _______________________________________________
> fpc-pascal maillist - fpc-pascal at lists.freepascal.org
> http://lists.freepascal.org/mailman/listinfo/fpc-pascal
More information about the fpc-pascal
mailing list