During the last half year, there has been several bugs related to C++ file streams, e.g., std::ifstream. Most bugs have been resolved by adding calls to ios::clear to clear the error state of the stream, or similar fixes. Other bugs were fixed by using C FILE instead.
Why, why, why, is file I/O so hard to implement in a reliable way in C++? I haven't done much work with files in C, but the things I've done work well. Same thing with python. Java's file I/O is just a joke (why do I need three classes to read a file?), but at is more reliable than C++.
Think twice before I use std::fstream again. You code might be fine on implementation of the C++ standard library, but will fail on another. Sad.