INTRODUCTION
                         TO THE GNU PROGRAMMING TOOLS

The Free Software Foundation has developed a complete set of system utilities
as part of the GNU Project.  You will use "g++" (a C++ translator) and "gdb"
(a debugger) as you work on your assignments for this course.

On most systems, it takes four steps to translate a C++ program into an
executable program:  preprocessing, compilation, assembly, and linking.  The
"g++" utility provides a convenient interface to accomplish these tasks.

For example, to translate the C++ program contained in "fileA.cpp":

  <prompt> g++ fileA.cpp

By default, the resulting executable program is stored in the file "a.out".

If the C++ program is contained in more than one file, you simply list all of
the relevant file names and "g++" does the processing steps in the correct
order (each file is translated into object code and then all are linked).

There are a number of useful options that you can use with "g++":

  -Wall    Issue warning messages for source code which is syntactically
           correct but appears to contain constructs you may wish to avoid.

  -g       Insert additional information into the executable program for use
           with a debugger (such as "gdb").

  -c       Halt the translation process after assembly and before linking (the
           resulting object code files end with ".o").

More than one option can be specified.  For example:

  <prompt> g++ -Wall -c fileB.cpp fileC.cpp

Here, "g++" will issue warning messages for any suspect statements it finds in
either "fileB.cpp" or "fileC.cpp".  It will also generate two object code
files ("fileB.o" and "fileC.o") that correspond to the two source code files.

The "gdb" debugger can be useful to assist you in locating execution-time
errors in your programs.  First, translate your source code program using
the "-g" option, then execute the debugger:

  <prompt> g++ -g fileA.cpp
  <prompt> gdb a.out

Once the debugger is executing, you can issue commands to control execution
of your program.  Some of the basic commands are listed below:

  run      Start executing your program.

  quit     Exit from the debugger.

  where    Identify the location where your program halted.

  list     Display the source code lines near the current position.

Additional information about "g++" and "gdb" is available via the "man"
utility and other on-line documents.