'How to close IStream?

How can i close IStream in c++?

c++stream


Solution 1:[1]

If you mean COM IStream, just call IUnknown::Release().

Solution 2:[2]

You can close file iostreams with ifstream::close. closing a istream doesn't really make sense - should it close the shell the program is started from?

You can flush an iostream to ensure the output is written

Solution 3:[3]

There are two standard subclasses of std::istream, which are closeable. If you want to close them in a context, where you only see the base class, you first need to cast to the instantiated subclass.

std::istream& is ....

// close is
std::ifstream* ifs = dynamic_cast<std::ifstream*>(&is);
if (ifs!=0)
{
    ifs->close();
}
else
{
    std::fstream* fs = dynamic_cast<std::fstream*>(&is);
    if (fs!=0)
    {
        fs->close();
    }
}

Sources

This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.

Source: Stack Overflow

Solution Source
Solution 1 Nemanja Trifunovic
Solution 2 Martin Beckett
Solution 3 Sam Ginrich

Related Questions