fundamentals of linkers as they apply to Xcode

I am working with libraries for the first time. The libraries in question are large, and there are a lot of them. Even after reading all the relevant material I could find on SO, I keep running into linker errors. Sometimes I manage to resolve them, but in the end I don't really feel like I understand what is going on.

Is there a good source for the basics of linkers -- preferably as they apply to Xcode, but if such does not exist, then just in general. The shorter it can be (while still explaining key concepts), the better. Sort of like a Kernighan and Ritchie f开发者_运维百科or linkers.

I am aware of the apple docs. I didn't find them particularly illuminating. The basics of libraries doc was more helpful, but it still left a lot of holes.

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This is a pretty basic overview:

http://en.wikipedia.org/wiki/Linker_(computing)

If there are concepts/terms above that don't make sense, feel free to edit your question or post a new one.