Tutorial on C pointers and arrays from a Java stan

Question

I'm currently a freshman in college, majoring in CS. I'm just about done with my "Intro to Computer Programming" class. I like it and feel like I'm learning a good bit.

A couple days ago, I read Joel's The Peril Of Java Schools. "A Linked List?" I thought, "those aren't even hard. We've done a bunch of those already in the class I'm in right now." Which is correct, because in Java, they're not that hard. But anyways, I tried to give writing one in C a try.

And it is SO HARD!

Joel was right, I think ... Java deals with so many little itsy-bitsy things for you that it's really not that hard. But I'm determined to overcome my school's Java-tude and learn how to write this dang linked list in C.

So I guess, instead of trying to ask lots and lots of little tiny questions, I am asking, does anyone know of a good (& free) online tutorial for learning C? Specifically, learning how to deal with pointers, and all those symbols (&, *, **, [] and how they work together) I'd like to think I'm already pretty proficient in Java, so I don't need the tutorials on how to write a "Hello, World!" program. But then I'm definitely not ready to get into any super-advanced C or C++ anything, because all I know is Java.

Any help appreciated!

Answer 1

This is for C++, not C; but up until about Chapter 3.7 or so talks about stuff at the machine level in a way that's useful for would-be C programmers.

Answer 2

There are numerous guides across the internet for learning pointers. Here's one: http://pweb.netcom.com/~tjensen/ptr/pointers.htm which I've used.

I'm also going to suggest this book to you: Hacking, the Art of Exploitation 2nd Ed.

This book will not make you a "hacker". Nothing but lots of reverse engineering / studying binary code, trial and error etc is going to do that. It does, however, introduce to you how you start doing these things and that comes down to a fundamental understanding of how C works, including pointers. Its introduction to assembly/C is one of the best I've seen because it runs you through several C examples and how you investigate what's going on with gdb, a command line debugging tool. That way you can see the C and see the assembly. This includes a fundamental understanding of what pointers are.

This book will as a side-effect give you an introduction to the stack and the heap, data structures etc. In short, reading the intro sections will give you a lot of benefit for the rest of your course.

Answer 3

Check and see if your curriculum requires Systems Programming. Its usually a 300-level sophomore course, and I'm enrolled for that next semester. It is heavily involved working with C+GCC in Unix.

Check your CS dept library, if one exists. I picked up a copy of K&R to work on through winter break.

Answer 4

Some tutorials:

• Moving from Java to C++
• Learning C from Java
• C for Java Programmers course (course notes and slides)

Some good pointer answers which might help:

• What are the barriers to understanding pointers and what can be done to overcome them?
• What is a void pointer and what is a null pointer?
• Arrays, what's the point?
• What do people find difficult about C pointers?
• Switching from Java to C++ - what's the easy way?
• Is Java pass by reference?

The first is a damn good read about pointers and their pitfalls, if you can get past the Pascal syntax.