关于指针

malloc与不使用malloc

 1 #include <stdio.h>

 2 #include <stdlib.h>

 3 

 4 

 5 typedef struct {

 6     int a;

 7     char * ch; 

 8     int aa; 

 9 }node;

10 

11 int main()

12 {

13     int *i = NULL;

14     int ii = 10; 

15     i = &ii;

16     printf("local %p\n", i); 

17     node * aa = (node*)malloc(sizeof(node));

18     printf("local %p\n", aa->ch);

19     if(aa->ch ==NULL){

20         printf("local %p\n", aa->ch);

21     }   

22     

23     node bb; 

24     printf("local %p\n", bb.ch);

25     free(aa);

26     return 0;

27 }

root@u18:~/cp/test# ./a.out
local 0x7fffe2aa515c
local (nil)
local (nil)
local 0x400640