how copy from one stringstream object to another in C++?

Question

I have stringstream object ss1

now I would like to create another copy from this one.

I try this

std::stringstream ss2 = ss1;

or

std::stringstream ss2(ss1)

neither works

The error message is like this

std::ios::basic_ios(const std::ios &) is not accessible from bsl::basic_stringstream, bsl::allocator>::basic_stringstream(const bsl::basic_stringstream, bsl::allocator>&).

Answer 1

As std::stringstream does not provide a copy constructor, you have to build it from the std::string ss1outputs:

std::stringstream ss2(ss1.str());

Answer 2

Indeed, streams are non-copyable. Depending on your usage, the following works quite well:

#include <cassert>
#include <iostream>
#include <sstream>

int main(void)
{
    std::stringstream ss1;
    ss1 << "some " << 123 << "stuff" << std::endl;

    std::stringstream ss2;
    ss2 << ss1.rdbuf(); // copy everything inside ss1's buffer to ss2's buffer

    std::cout << ss1.str() << std::endl;
    std::cout << ss2.str() << std::endl;
}