How to loop over a binary file in Python in chunks

Question

I\'m trying to use Python to loop over a long binary file filled with 8-byte records.

Each record has the format [ uint16 | uint16 | uint32 ]
(which

Answer 1

The iter builtin, if passed a callable and a sentinel value will call the callable repeatedly until the sentinel value is returned.

So you can create a partial function with functools.partial (or use a lambda) and pass it to iter, like this:

with open('foo.bin', 'rb') as f:
    chunker = functools.partial(f.read, 8)
    for chunk in iter(chunker, b''):      # Read 8 byte chunks until empty byte returned
        # Do stuff with chunk