#include <graphics.h>
int getpalettesize(void);
 

getpalettesize is used to determine how many palette entries can be set
for the current graphics mode. For example, the EGA in color mode returns
16.

/* getpalettesize example */
 
#include <graphics.h>
#include <stdlib.h>
#include <stdio.h>
#include <conio.h>
 
int main()
{
   /* request autodetection */
   int gdriver = DETECT, gmode, errorcode;
   int midx, midy;
   char psize[80];
 
   /* 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 */
   }
 
   midx = getmaxx() / 2;
   midy = getmaxy() / 2;
 
   /* convert palette size info into string */
   sprintf(psize, "The palette has %d modifiable entries.",getpalettesize
());
 
   /* display the information */
   settextjustify(CENTER_TEXT, CENTER_TEXT);
   outtextxy(midx, midy, psize);
 
   /* clean up */
   getch();
   closegraph();
 
   return 0;
}

setallpalette setpalette

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