LinuxQuestions.org - pointer to structure

LinuxQuestions.org (/questions/)

- Programming (https://www.linuxquestions.org/questions/programming-9/)

- - pointer to structure (https://www.linuxquestions.org/questions/programming-9/pointer-to-structure-101935/)

pointer to structure

I have two questions about the program that is at the bottom of the post:
First, if I write a program

Code:

int* ip=&i;

then I can use

Code:

cout<<ip;

to output the address of i; similar to this, can I output the address of s1.c by the command that contains the words sp1? I ask this because I have written

Code:

structure3* sp1=&s1;

Second, is the address of s1.c really aB? Why is not some value as 0x... as the address of s1.i?

Code:

#include<iostream>

using namespace std;



typedef struct struct3 {

  char c;

  int i;

} structure3;

int main ()

{

  structure3 s1, s2;

  structure3* sp1=&s1;

  structure3* sp2=&s2;

  s1.c='a';

  s1.i=1;

  sp2->c='b';

  sp2->i=2;

  

  cout<<"sp1->c="<<sp1->c<<endl

      <<"sp1->i="<<sp1->i<<endl;

  cout<<"s2.c="<<s2.c<<endl

      <<"s2.i="<<s2.i<<endl;

  cout<<"&s1.c="<<&s1.c<<endl

      <<"&s1.i="<<&s1.i<<endl;

}



[root@localhost a_pointers]# ./simple_struct3_c

sp1->c=a

sp1->i=1

s2.c=b

s2.i=2

&s1.c=a

B

&s1.i=0xbfffda44

[root@localhost a_pointers]#

Thank you.

Re: pointer to structure

Quote:

Originally posted by Xiangbuilder
cout<<"&s1.c="<<&s1.c<<endl
}
[root@localhost a_pointers]#[/code]Thank you. [/B]

c is a char, so &s1.c is interpreted like char* and cout think that it has to write a string (char*) and it so this.

int * a = new int;
cout << a << endl; // put the address of a (int*)

char * s = "i'm a string";
cout << s << endl; // put a string, not the address of s;

So if U want to get the address,
U need to write cout << (int*)(&s1.c) << endl;

Thank you.
I feel I can understand some parts of your post,
and I can't understand others because of my poor c++ knowledge.
Howeve, I have downloaded it for future learning.
Thank you.