One can only learn a language one time, so I've got a hard time recommending first books. But I definitely second the recommendation for the second book here ;) Hanson's style is a bit idiosyncratic, with his somewhat Modula-3-ish naming style and literate programming use, but there are a lot of usable data structures in there, and I especially like that the focus is on the module level, not on the algorithms themselves. Now, having said that, if you're in a particularly weird sub-domain of C, books from there might supersede or at least color a lot of what you're doing on a day to day basis. In the days of yore, if you wanted to do Win16/Win32 programming, getting to work with your Petzold early is a good idea, and I would assume the same to be true if you do glib/gobject based Gtk programming. Two free resources that looked good to me and that I forwarded in the past were "An Introduction to the C Programming Language and Software Design"[1] by Tim Baily and "Beej's Guide to C Programming"[2]. Those are a bit more concise than your average intro to C book, but for some paths (prior experience, quick headway to C++ etc), they might be sufficient.…
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