判断大端小端

int checkCPU( )
{
    {
           union w
           {  
                  int a;
                  char b;
           } c;
           c.a = 1;
           return(c.b ==1);
    }
}

 int i = 1;
    char *cp = (char *)&i;
    if (*cp)  
        printf("Little Endian/n");
    else 
        printf("Big Endian/n");