A lecture by Tom Buono on making a C++ library

  For Tom: 25 extra credit points toward lab grades (up to max of 100% on lab
    portion of course).

  If you would like an opportunity to do a lecture for extra credit,
  let me know, and I'll help you find a topic.   We might also do this
  on an "impromptu" basis, as we did today.


e
ndianTesters.cc

endianTesters.h---->header file, function Prototypes


lab04bs2.cc  ---> #include "endianTesters.h"

         include "foo.h" means look in current directory
         include <foo.h> means look in "system" directories for header files
          (can add to system directories with the -I flag)


#include'ing a .h file means "copy and paste this file into the 
    file at the point where the #include appears"


CC -c lab04bs2.cc
   gives us a .o file lab04bs2.o

    -c means compile only, don't link  .... just make a .o file


   It is not a fully functioning program on its own.
    
   .o file is executable instructions for ONLY the stuff in the .cc file
   you compiled.

    It has to be linked together with other .o files (including
     system libraries like iostream.o and cmath.o, etc. ) to make
     a complete executable.  At link time, symbols (i.e. the names of
      functions and variable) are turned into actual numeric addresses.


Linking Step:

    Combine all the .o files into one big file....


    The .o files for the files that WE made... plus all the .o files
    that are behind the scenes...

CC endianTesters.o lab04bs2.o -o lab04bs2

  The name usually is chosen from the .o file that contains the main.

  


The order of the .o files is arbitary.... the only thing that is
required is that the -o must come immediately before the name
of the executable file.


(If you don't put "-o something", the executable ends up in a file
named a.out )