Erasing and creating files and directories

Let's consider the following lines of code:

    std::ofstream ofs("dir/subdir/file.txt"); 
    ofs << "Boost.Filesystem is fun!"; 

In these lines, we attempt to write something to file.txt in the dir/subdir directory. This attempt will fail if there is no such directory. The ability to work with filesystems is necessary for writing a good working code.

In this recipe, we'll construct a directory and a subdirectory, write some data to a file, and try to create symlink. If the symbolic link's creation fails, erase the created entities. We should also avoid using exceptions as a mechanism of error reporting, preferring some kind of return codes.

Let's see how that can be done in an elegant way using Boost.

...