[vault_]

Why wasn't I aware of this guide last week when I had to write a kernel driver for my OS class?!

One thing that's surprised me with Linux development is how nice the APIs are to work with. Things like the file_operations struct, and the linked list stuff are very well thought out and easy to use (as easy as they could be for C programming).

My only complaint is that a lot of the written documentation is out of date about a number of topics. As the kernel has evolved it's gained and lost a number of APIs and depending on when resources were published they may say a number of conflicting things about how to carry out a task (registering a character device and getting it in /dev is the big one that comes to mind).

[azernik]

This is why kernel hackers tend to say "Use the Source, Luke!" instead of pointing you at documentation. The one exception is documentation that talks about the high-level design of a feature (e.g. Documentation/pi-futex.txt), which is usually updated whenever there's a complete rewrite or major design change.