Recs.
Updated
The canonical text on the topic, written by the authors of the language (and Unix). The book is not easy but is slim and direct, pulls no punches, and requires patience and careful study.
It is particularly appropriate for individuals with good programming experience but without extensive C experience.
Beginner programmers may find its pace a little overwhelming.
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Pros
Cons
Con Teaches bad style
The K&R style works for old Unix mainframe command-line programs that exit after a simple task and leave the cleanup to the OS; where input is only from trusted experts; and most functions are only called internally to the program. The environment is very different today. This style will get your server owned by hackers, or crash it due to a memory leak, etc. You will have to unlearn what you've learned from this book to use C correctly in the real world today.