[linux c/c++] 位域操作

#include <stdio.h>
 
struct bitmap{
         int a:2;
         unsigned int b:4;        
         int :2;
         int c:6;
         unsigned int d:2;
 };


 int main(int argc ,char ** argv)
 {
         struct bitmap tmp;
         tmp.a=1;
         tmp.b=8;
         tmp.c=20;
         tmp.d=0x3;

         printf("%d,%d,%d,%d\n",tmp.a,tmp.b,tmp.c,tmp.d);
 }