title: defining structures globally in c++
body: <p>there was a somewhat detailed thread (228684) on how to globally (using extern struct) declare a structure that could be seen in more than 1 c++ file, but I can not figure out exactly how to do it (there was a lot of discussion about do this, do that, maybe do this, try this, etc...). </p>
  
  <p>couuld someone please post a very simple example of how to declare a structure that could be seen in 2 separate c++ files?  If I put all my functions in the same file as the main it works fine, but when I try to split the functions out in different files I cannot get it to compile. </p>
  
  <p>Things I am unclear on...
  Should I typedef the structure?
  Do I define the structure in a header file and include that header in each c++ source file?
  Do I need the #ifndef macro in the header file?
  Do I declare the structure extern in the header?</p>