From: "J.E." <cellis AT voyageur DOT ca>
Newsgroups: comp.os.msdos.djgpp
Subject: Allegro Problems
Date: Sat, 06 Sep 1997 18:37:41 -0500
Organization: Bell Network Solutions
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Message-ID: <3411E944.52E6@voyageur.ca>
Reply-To: cellis AT voyageur DOT ca
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To: djgpp AT delorie DOT com
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Hello.  I just downloaded Allegro v2.2, but I am having some serious
problems with the screen scrolling function.  I wrote this code to test
the scrolling (something new to me):

------------------------------------------------------------------------
#include <stdio.h>
#include <stdlib.h>
#include <conio.h>
#include "allegro.h"

int main()
{
  int index, x, y, c;
  allegro_init();
  set_gfx_mode(GFX_VGA, 320, 200, 1024, 1024);
  clear(screen);
  for (y = 0; y < 1024; y++)
   for (x = 0; x < 1024; x++)
   {
    c++;
    if (c > 255) c = 0;
    putpixel(screen, x, y, c);
   }
  getch();
  for (index = 0; index < 300; index++)
   scroll_screen(index, 0);
  for (index = 0; index < 300; index++)
   scroll_screen(300, index);
  getch();
  scroll_screen(0, 0);
  getch();
  exit(0);
}
------------------------------------------------------------------------


After compiling with no errors, I got the following message at run-time:

------------------------------------------------------------------------
Shutting down Allegro
Exiting due to signal SIGSEGV
General Protection Fault at eip=000000f2
eax=0001703d ebx=00001589 ecx=0006c124 edx=00000000 esi=00002b8f
edi=00000a86
ebp=00000000 esp=0006c120 program=C:\DJGPP\BIN\BUFF2.EXE
cs: sel=023f  base=829eb000  limit=0007ffff
ds: sel=0247  base=829eb000  limit=0007ffff
es: sel=0247  base=829eb000  limit=0007ffff
fs: sel=0237  base=000105f0  limit=00003fff
gs: sel=0257  base=00000000  limit=ffffffff
ss: sel=0247  base=829eb000  limit=0007ffff

Call frame traceback EIPs:
  0x000000f2
------------------------------------------------------------------------

Any help on this would be greatly appreciated.  BTW, thanks to Shawn H.
for making such an awesome lib!  

Jordan Ellis   <cellis AT voyageur DOT ca>