Parse Binary Records Safely in Python with struct
Binary files and network messages often begin with fixed-width fields: a four-byte signature, a one-byte version, a two-byte payload length, or a four-byte identifier. Those fields are easy to describe on paper but surprisingly easy to parse incorrectly in code. The difficult part is not converting bytes to integers. It is preserving the binary layout contract: exactly which byte belongs to which field, which byte order is used, how wide each value is, and what should happen when the input is incomplete or malformed.