title: Understand xcode linking (ld)
body: <p>After running into linker errors one time too many, I have come to the conclusion that I really need to understand how ld works, rather than just asking SO for black magic fixes everytime something doesn't work.  I've found the <a href="http://developer.apple.com/library/mac/#documentation/Darwin/Reference/Manpages/man1/ld.1.html" rel="noreferrer">Mac OS ld man pages</a> which do provide some information, but as they say, they are intended for people who already understand ld.  How can one gain that understanding?</p>
  
  <p>Part of the problem is that there are different flavors of ld -- unix and gcc at a minimum -- and does clang have its own flavor?  So I'm not sure what docs apply.</p>