c++ - Copying "this" pointer to a buffer -

i need copy address of this pointer buffer , re-typecast elsewhere. aware can it, if outside class. but,here need use member function given in sample code provided here:

#include <iostream> #include <cstring>  class myclass { public:     myclass(const int & i)     {         id = i;     }     ~myclass()     {      }     void getaddress(char* address)     {         memcpy(address, this, sizeof(this));             }     void print() const     {         std::cout<<" id: "<<id<<std::endl;                }  private:     int id;  };  int main() {     myclass myclass(100);     std::cout<<"myclass: "<<&myclass<<std::endl;      myclass.print();      // need copy address buffer, sepcifically using function follows , retrieve later     char tmp[128];     myclass.getaddress(tmp);      // retreiving pointer        myclass* myclassptr = (myclass*) tmp;     std::cout<<"myclassptr: "<<myclassptr<<std::endl;     myclassptr->print();      return 0; } 

my output:

myclass: 0x7fff22d369e0  id: 100 myclassptr: 0x7fff22d369f0  id: 100 

as can see 2 addresses different. however, both function printing id correctly. wonder how happens! need correct method.

correct version of getaddress():

void getaddress(char* address) {     const myclass* tmp = this;     memcpy(address, &tmp, sizeof(this)); } 

update:

// retreiving pointer    // myclass* myclassptr = (myclass*) tmp; - wrong myclass* myclassptr = *( (myclass**) tmp );