#include <graphics.h> int getmaxcolor(void);
For example, on a 256K EGA, getmaxcolor always returns 15, which means that any call to setcolor with a value from 0 to 15 is valid. On a CGA in high-resolution mode or on a Hercules monochrome adapter, getmaxcolor returns a value of 1.
/* getmaxcolor example */ #include <graphics.h> #include <stdlib.h> #include <stdio.h> #include <conio.h> int main(void) { /* request autodetection */ int gdriver = DETECT, gmode, errorcode; int midx, midy; char colstr[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; /* grab the color info. and convert it to a string */ sprintf(colstr, "This mode supports colors 0..%d", getmaxcolor()); /* display the information */ settextjustify(CENTER_TEXT, CENTER_TEXT); outtextxy(midx, midy, colstr); /* clean up */ getch(); closegraph(); return 0; }