结构体大小的判断

/*
 * test.c
 *
 * Created on: 2010-12-21
 * Author: qiang
 */

#include <stdio.h>
#include <stdlib.h>

typedef struct{
    char a;
    char b;
    int c;
    char d;
}Test;

int main()
{
    Test *test;

    test = (Test*)malloc(sizeof(Test));

    int len = sizeof(Test);

    printf("len test: %d \n",len);
    printf("a addr: %p \n",&(test->a));
    printf("b addr: %p \n",&(test->b));
    printf("c addr: %p \n",&(test->c));
    printf("d addr: %p \n",&(test->d));


    return 0;
}

结果如下：
len test: 12
a addr: 0x85f3008
b addr: 0x85f3009
c addr: 0x85f300c
d addr: 0x85f3010