I've for long known the C syntax and I like it very much. I can easily understand C programs and I've myself written lots and lots of Win32 API code. However, since my mainstay has been VB, I'm not at all confident of calling myself a C programmer and I still believe I do not know C. That is true because when I look at projects on SourceForge, I do not see myself as capable as re-creating that stuff. I can't write sound editors, zip/compression apps, binary editors et al.

As a self-analysis, I believe I know the C syntax but I score rather measley on the vocabulary. So I ask you gurus: what's your advise to someone who's known only the C syntax for a long period of time now, say more than 6 years, has done some Windows Programming but nothing else in C. What's your tip to this self-learner who wants to take the next step in writing apps alike those that feature on SourceForge. Where do I look next? How do I improve my C vocabulary? Should I first browse the standard library documentation? What next? I believe C in itself is such a small language with a very general function set dealing with basic data types in the standard library. Am I right in assuming that for doing a particular non-generic application like the ones mentioned above, I'd have to depend on a library and read its documentation? Do these developers developing, say, a database application that provides a C front-end connecting to a MS SQL Server database do the connection thing from scratch in C or do they rely on an external pre-packaged library?

How do I proceed improving my vocabulary? I want to quickly begin writing a useful application that I can proudly boast of.