#include <dos.h>
void mouse_test()
{
    _AX = 0;             //调用0号功能
    geninterrupt(0x33);
    if(_AX == -1)      //若安装返回-1，否则返回0
        printf("mouse installed %d buttons\n", _BX);
    else
        printf("mouse not installed\n");
    getch();
}