#include <graphics.h>
void graphdefaults(void);
 

graphdefaults resets all graphics settings to their defaults:
    * sets the viewport to the entire screen.
    * moves the current position to (0,0).
    * sets the default palette colors, background color, and drawing
color.
    * sets the default fill style and pattern.
    * sets the default text font and justification.

/* graphdefaults example */
 
#include <graphics.h>
#include <stdlib.h>
#include <stdio.h>
#include <conio.h>
 
int main(void)
{
   /* request autodetection */
   int gdriver = DETECT, gmode, errorcode;
   int maxx, maxy;
 
   /* initialize graphics and local variables */
   initgraph(&gdriver, &gmode, "");
 
   /* read result of initialization */
   errorcode = graphresult();
   if (errorcode != grOk) {  /* an error occurred */
printf("Graphics error: %s\n", grapherrormsg(errorcode));
 
printf("Press any key to halt:");
getch();
exit(1);   /* terminate with an error code */
   }
 
   maxx = getmaxx();
   maxy = getmaxy();
 
   /* output line with nondefault settings */
   setlinestyle(DOTTED_LINE, 0, 3);
   line(0, 0, maxx, maxy);
   outtextxy(maxx/2, maxy/3, "Before default values are restored.");
   getch();
 
   /* restore default values for everything */
   graphdefaults();
 
   /* clear the screen */
   cleardevice();
 
 
 
   /* output line with default settings */
   line(0, 0, maxx, maxy);
   outtextxy(maxx/2, maxy/3, "After restoring default values.");
 
   /* clean up */
   getch();
   closegraph();
   return 0;
}

initgraph setgraphmode

  no output of example at the moment
  do not hesitate and add it...