From:	Radical NetSurfer <radsmail AT juno DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Teleprompter Crashes :(
Date:	Wed, 01 Nov 2000 07:48:40 -0500
Message-ID:	<s1400tg34ala59dthjf164891oko8j0l43@4ax.com>
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To:	djgpp AT delorie DOT com
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Reply-To:	djgpp AT delorie DOT com

WHY does the following code (??) cause my program 
to Seg-Fault upon termination ??

PLEASE help me to understand this once and for all.
Using Allegro 3.12

This program is functional, works with keyboard input
or taking input from a text file ( Charg  < text.txt )


/**********************************************
   When the Lower-Right corner is reached, the screen
   is Scrolled and the Cursor Homed ONLY _after_ the
   next keypress is received! (desired)
   Input: Using Keyboard,
  Output: Display CharGen Text
    Uses: LocX, LocY for INITIAL Positions
Features:Actually performs a functional scroll!
***********************************************/
void bmptty(void) {
char temp[10];
int xs, ys, ch;
int line;

    xs = LocX;  //Initial Cursor Starting Position
    ys = LocY;  //Coords are 0,0 based

    line = 0;
    for(;;) {
     ch = getch();
   
     if ( ch == 27 ) break;
     if ( ch==13 ) { xs = 0; ys += 64; ++line; }

     if ( ch == 8 ) { 
               if ( xs > 41 ) { xs -= 42; }
             }
     if ( ch==12 ) { clear_to_color(screen, 0); }
     if ( ch < 32 ) continue;

     if ( ys > 512 ) { xs = 0; ys = 8*64;
                       //clear_to_color(screen, 0);
                       bmpscroll();   //<-- rem this out won't matter!
                     }

     sprintf(temp,"G:\\DJGPP\\CharGen\\Courier44\\Char%d.bmp", ch );
//   sprintf(temp,"Char%d.bmp", ch );

//if ( ) { continue; } //Check for existance of specific FontBMP !!

     the_image = load_bitmap(temp, the_pallete);
 if ( the_image == NULL ) { sound( 1440 ); delay(500);  nosound(); } 
     set_pallete(the_pallete);  //might be needed for 256BMP's

     blit(the_image, screen, 0, 0, xs, ys, the_image->w,
the_image->h);

     destroy_bitmap(the_image); //NECESSARY?
//   the_image = NULL;

     xs+=42; //Next whole-char position
     if ( xs >= 798 ) { xs = 0; ys += 64; }
    }
}

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