Question

I’m novice programmer and am writing a simple wav-player in C as a pet project. Part of the file loading process requires reading specific data (sampling rate, number of channels,…) from the file header.
Currently what I’m doing is similar to this:

1. Scan for a sequence of bytes and skip past it
2. Read 2 bytes into variable a
3. Check value and return on error
4. Skip 4 bytes
5. Read 4 bytes into variable b
6. Check value and return on error

…and so on. (code see: https://github.com/qgi/Player/blob/master/Importer.c)

I’ve written a number of helper functions to do the scanning/skipping/reading bit. Still I’m repeating the reading, checking, skipping part several times, which doesn’t seem to be neither very effective nor very smart. It’s not a real issue for my project, but as this seems to be quite a common task when handling binary files, I was wondering:
Is there some kind of a pattern on how to do this more effectively with cleaner code?

Answer 1

Most often, people define structs (often with something like #pragma pack(1) to assure against padding) that matches the file’s structures. They then read data into an instance of that with something like fread, and use the values from the struct.