上午上《编译原理》的时候听老师谈到了C语言的指针的问题，有些疑问，所以回到宿舍进行了实验验证。 
 
 
 
当函数参数是个指针的时候，当调用这个函数时，此函数的形参的得到的是指针本身，还是他的一个副本？如下代码：
#include "stdio.h" 
  
 void change1(int* d) 
 { 
     printf("address_d = %d  d = %d  *d = %d\n", &d, d, *d); 
     int s = 4; 
     d = &s; 
     printf("address_d = %d  d = %d  *d = %d\n",&d, d, *d); 
 } 
  
 void change2(int *e) 
 { 
     *e = 5; 
 } 
  
 int main() 
 { 
     int *p(NULL); 
     int *q(NULL); 
     int a(1); 
     while(a) 
     { 
         scanf("%d", &a); 
         printf("address_a = %d  a = %d\n", &a, a); 
         p = &a; 
         q = p; 
                 printf("address_P = %d  p = %d  *p = %d\n", &p, p, *p); 
                 printf("address_q = %d  q = %d  *q = %d\n", &q, q, *q); 
         change1(q); 
                 printf("address_q = %d  q = %d  *q = %d\n", &q, q, *q); 
         change2(q); 
         printf("address_a = %d  a = %d\n", &a, a); 
         printf("address_q = %d  q = %d  *q = %d\n", &q, q, *q); 
                 printf("address_P = %d  p = %d  *p = %d\n", &p, p, *p); 
     } 
 } 
 
 
 
 
 作者 wche1990