713: Highlights

• Header files should contain class definitions, global variable declarations, and function prototypes for every class, global variable, and function that you expect to appear in more than one file.
• You may include member-function definitions in the bodies of class definitions that appear in header files. Externally defined member-function definitions must appear in source-code files; they cannot appear in header files that are included in more than one file.
• If you want to declare an ordinary function, then leave behind a function prototype:

  return data type function name (data type of parameter 1, 
                                    ..., 
                                    data type of parameter n) 
  

• If you want to declare a global variable, then instantiate the following pattern:

  extern data type variable name; 
  

• You can declare functions and variables as often as you like. You can define them only once.
• If you want to compile a set of files independently, then include appropriate header files and instantiate the following pattern:

  CC -c first source specification ... 
  

• If you want to link together a set of independently compiled files to form a working program, then instantiate the following pattern on one line:

  CC -o executable file specification 
        first object file specification 
        ...