关于framerbuffer写数据显示问题

DBOYaoao

1. int main()
   
2. {
   
3.     struct fb_var_screeninfo vinfo;
   
4.     struct fb_fix_screeninfo finfo;
   
5.     short *fbbuf = NULL;
   
6.     int fd;
   
7.     fd = open("/dev/fb0",O_RDWR);
   
8.     if(ioctl(fd,FBIOGET_VSCREENINFO,&vinfo) < 0)
   
9.     {
   
10.         return -1;
    
11.     }
    
12.     printf("x is :%u\ny is :%u\n",vinfo.xres,vinfo.yres);
    
13.     unsigned int bpp = vinfo.bits_per_pixel;
    
14.     printf("per pixel is %u\n",bpp);
    
15.    
    
16.     unsigned int screensize = vinfo.xres*vinfo.yres*bpp/8;
    
17.     fbbuf = (short*)mmap(0,screensize,PROT_READ | PROT_WRITE,MAP_SHARED,fd,0);
    
18.     unsigned int i = 0;
    
19.     for(;i<screensize;i++)
    
20.     {
    
21.         
    
22.         *(fbbuf+i) = 0;
    
23.     }
    
24.     close(fd);
    
25.     return 0;
    
26. }

复制代码

代码如上：我想做的就是网framebuffer中写入数据，来查看是否屏幕上有什么颜色改变的反映，可是没有任何反应程序，哪位大牛知道的帮帮小弟！多谢了！