Question

Suppose I have a file opened with the C syntax

FILE* fp = fopen("whatever.txt", "w");
// Library function needs FILE* to work on
libray_function(fp);

// Now I'd like to copy the contents of file to std::cout
// How???

fclose(fp);

I would like to be able to copy the contents of that file in a C++ ostream (like a stringstream or maybe even std::cout). How can I do that?

Answer 1

Close it first.

fclose(fp);

Then open again

string line;
ifstream myfile ("whatever.txt");
if (myfile.is_open())
{
    while ( myfile.good() )
    {
        getline (myfile,line);
        cout << line << endl;
    }
    myfile.close();
}