Question

If I need to, I suppose I could write my own version using streams, but this seems like a basic piece of functionality which should be out there somewhere.

Answer 1

The boost::filesystem library contains a copy_file function. It is documented
at the boost website.

It can be used like this

#include <string>
#include <boost/filesystem.hpp>

std::string sourcePath = "./sourceFile.txt";
std::string destPath  = "./destFile.txt";
boost::filesystem::copy_file(sourcePath, destPath, boost::filesystem::copy_option::overwrite_if_exists);