判断结构体中某成员的位置

#define PARAM_OFFSET(Strct, Field)    ((unsigned long)&(((Strct *)0)->Field))

struct abc
{
    int a;
    int b;
    int c;
};

void main()
{
    printf("%d/n", PARAM_OFFSET(abc, a));
    printf("%d/n", PARAM_OFFSET(abc, b));
    printf("%d/n", PARAM_OFFSET(abc, c));
}

/*
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Press any key to continue
*/