I'm getting empty string when i pass parameter by reference

Asked Sep 01 '21 at 12:12

Active Sep 01 '21 at 12:12

Viewed 24 times

I'm new to c++ , I'm working on a project that uses std::string and then converts that string to char* to be used in functions that are going to be exported.

However, I'm getting an empty string when I debug it.

#include <iostream>
#include <string>

void fun(char* &x, char* &y)
{
    std::string tmp = "hello"; 
    std::string temp = "world";
    x = &tmp[0];
    y = &temp[0];

}
int main()
{
    char* x;
    char* y;

    fun(x, y);
}

Best regards.

asked Sep 01 '21 at 12:12

user3374161

`tmp` and `temp` go out of scope and are destroyed when `fun` ends. The pointers are no longer valid. – Johnny Mopp Sep 01 '21 at 12:15
you should use [`std::string::c_str`](https://en.cppreference.com/w/cpp/string/basic_string/c_str) to get a pointer to the strings buffer, though that pointer is also only valid as long the string is alive – 463035818_is_not_a_number Sep 01 '21 at 12:16
can you give me an example for that situation – user3374161 Sep 01 '21 at 12:34

I'm getting empty string when i pass parameter by reference

0 Answers0