I would expect C to run circles around the same operation under Python.
You should probably only expect C to run circles around the same operations when those operations implemented entirely in Python. In the specific (trivial) example given, I wouldn't expect Python to be much slower:
for root, files, dirs in os.walk(path) for f in files: try: x = file(f, 'rb') data = x.read() x.close()
Remember that CPython is implemented in C, and so all the builtin types (including file) basically execute C code directly. My experience with Python file objects is that they are quite fast when you're doing simple things like the example above. (In fact, I usually find that Python is faster than Java for things like this.)
Of course, the example above is almost certainly omitting some code that really gets executed, and without knowing what that code does, it would be difficult to predict exactly what performance gain you would get from reimplementing it in C. Profile the app first, find out where the tight spots are, and then reimplement in C if necessary (often, it isn't).
STeve -- http://mail.python.org/mailman/listinfo/python-list
