Mouse programing within a window.c

//mouse programming within a window by Akshay

#include<graphics.h>
#include<stdio.h>
#include<conio.h>
#include<dos.h>
union REGS in,out;

void callmouse()
{
in.x.ax=1;
int86(51,&in,&out);

}
void restrictmouseptr(int x1,int y1,int x2,int y2)
{
in.x.ax=7;
in.x.cx=x1;
in.x.dx=x2;
int86(51,&in,&out);
in.x.ax=8;
in.x.cx=y1;
in.x.dx=y2;
int86(51,&in,&out);
}
void main()
{
int x,y,cl,a,b;
clrscr();

int g=DETECT,m;

initgraph(&g,&m,"Akshay");

rectangle(100,100,550,400);
callmouse();
restrictmouseptr(100,100,550,400);

getch();
}