From:	bitland AT aol DOT com (Bitland)
Newsgroups:	comp.os.msdos.djgpp
Subject:	malloc/new once again
Lines:	37
NNTP-Posting-Host:	ladder02.news.aol.com
Date:	25 Sep 1998 07:59:23 GMT
Organization:	AOL Bertelsmann Online GmbH & Co. KG http://www.germany.aol.com
Message-ID:	<19980925035923.00799.00001778@ng85.aol.com>
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Hello !
I got version 2.8.1 and still have malloc-problems. Allocating memory in an
absolutely simple program and freeing it in the next moment, displaying the
memory with  __dpmi_get_free_memory_information(&dfmi); gives confusing
memory values and then the memory slowly gets low.

Here's the main loop (simulating making allegro bitmaps), with MAXSIZE 1024,
CDEPTH 32 and MAPS so, that you cannot allocate more than you have, but be sure
to get closely to the limit, then the effect comes faster.

  do
  {
    for (i=0;i<MAPS;i++)
    {
      hm[i] = malloc((CDEPTH>>3)*(random()%MAXSIZE * (random()%MAXSIZE)));
      if (!hm[i])     
        textout(screen,font,"there it is !",200,20,COLWHITE);   /* via allegro
*/
    }
    checkmem("allocated");

    for (i=0;i<MAPS;i++)
      if (hm[i])
        free(hm[i]);
    checkmem("freed    ");

  } while (!keypressed());

After this, you SOMETIMES cannot get a large memory block !
And 'there it is' shouldn't appear at all, what if allocated with 'new' without
a newhandler ? The program crashes...

Any idea without a do-it-yourself-memory-manager ?
Please mail me
Andy Kluge       BITLAND AT AOL DOT COM

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