As we said in the preface to the first edition, C "wears well as one's experience with it grows." With a decade more experience, we still feel that way.

If you had done something twice, you are likely to do it again.

Get the weirdnesses into the data where you can manipulate them easily, and the regularity into the code because regular code is a lot easier to work with

The most effective debugging tool is still careful thought, coupled with judiciously placed print statements.

... it is a fundamental principle of testing that you must know in advance the answer each test case is supposed to produce. If you don't, you are not testing; you are experimenting.

Don't document bad code - rewrite it.

90% of the functionality delivered now is better than 100% delivered never.