1. TA: Maya Rodrig Our C++ guru: Nic Bone
CSE 326
TA: Maya Rodrig
Our C++ guru: Nic Bone

2. Linux machines at UW Machine Names: Ceylon, Sumatra, Fiji, Tahiti
Access
Use X-terminals in back of Sieg 329 (click on one of the Linux machines)
Use Windows machines

3. Opening an XTERM on a Windows machine
Log into the CSEPCLAB domain
Start -> Programs -> Reflection -> Reflection X
“X Client Manager” should open
Select the “linux.rxc” connection template
Select the KERBERIZED TELNET method
Enter the host name (fiji, ceylon, tahiti, sumatra)
Click Connect
An XTERM should open (if not, ask for help)

4. Unix Manual: ‘man’ Keys: q – exit man Page Up Page Down The command:
apropos copy
Finds all man pages that contain
the word “copy” in their
descriptions. Useful for finding
out about a command.
Keys:
q – exit man
Page Up
Page Down

5. Make Project Directory
fiji% mkdir cse326
fiji% cd cse326
fiji% mkdir proj1
fiji% cd proj1
fiji% pwd
/homes/iws/rodrig/cse326/proj1
fiji% ls /homes/iws/rodrig/cse326/proj1
fiji%
More UNIX commands are at:

6. Look at files in a class directory

7. File Permissions ‘w’ here means I can write to the files, but no-one
else can

8. chmod (thanks to Nic Bone)
> I'm having trouble understanding the man files. How would I change permission to
> -rwxr--r--
>
> What's the syntax?
The easy-to-remember way to do this is to type:
% chmod a+r file
% chmod u+wx file
% chmod go-wx file
Meaning of the symbols:
r: read w: write x: execute u: user g: group o: other a: all three (u, g, and o)
+: add this permission
-: remove this permission
You can also set the permissions with one command using a numeric code of three numbers in the range The first number corresponds to user permissions, the second to group permissions, and the third to other (or world) permissions. Read permission is +4, write permission is +2, and execute permission is +1. So to change permission to -rwxr--r--, we would type:
% chmod 744 file
Nic.

9. How to compile the program

10. How to run your program
./ is important. By default, Linux won’t search the current
directory for a program. So you have to explicitly tell it
(eventually, you can change your PATH environment
variable)
< means get the input from the file to the right (inputs/maze1.txt),
instead of the keyboard. If you don’t put this in, the program will
expect you to type the input on the keyboard – quite a hassle!

11. Edit runmaze.cpp – forgot &
Darn, now
we lost this
shell until
we close
emacs

12. Edit runmaze.cpp
Current line number

13. Emacs keys CTRL-X S (hold down control for both letters) CTRL-X C
Save your work
CTRL-X C
Exit emacs
CTRL-G
Abort current command (if you accidentally typed something wrong)
More:
(Quick intro)
(official documentation)

14. Intro to make – project file dependencies

15. 2 lines from Makefile
runmaze : runmaze.o MazeRunner.o RandomMazeRunner.o Maze.o SquareMaze.o VisualizeSquareMazeRunner.o GPKernel.o
g++ -o runmaze -g runmaze.o MazeRunner.o RandomMazeRunner.o Maze.o SquareMaze.o VisualizeSquareMazeRunner.o GPKernel.o -L/usr/X11R6/lib -lX11
runmaze (executable file)
is dependant on a bunch of
object files
If runmaze doesn’t exist, or
is out of date (relative to
object files), here’s how to
build it
WARNING: this is a tab
character. It has to be tab,
and can’t be spaces. Those
are the rules.

16. g++ linking command line
-o runmaze
Call the output file ‘runmaze’ (instead of a.out, which is the default) -g
Include debugging information, so you can use a debugger
-L/usr/X11R6/lib -lX11
Include X-Windows libraries (for visualization part)
g++ -o runmaze -g runmaze.o MazeRunner.o RandomMazeRunner.o Maze.o SquareMaze.o VisualizeSquareMazeRunner.o GPKernel.o -L/usr/X11R6/lib -lX11

17. 2 lines for runmaze.cpp (well, technically runmaze.o)
runmaze.o : runmaze.cpp Maze.h SquareMaze.h MazeRunner.h RandomMazeRunner.h VisualizeSquareMazeRunner.h
g++ -Wall -c -g runmaze.cpp
The object file runmaze.o
depends on runmaze.cpp +
some .h files
The infamous tab
character strikes
again!
If runmaze.o doesn’t exist, or is out of date
relative to the files past the colon ( : ), here’s
how to build it with g++.

18. g++ compiling flags -c -Wall -g
Only compile, don’t link – we’ll let make decide when to link.
-Wall
g++ will give us all of the Warnings it can think of. Maybe it’ll help us find a bug quickly. -g
Add debugging information.
Is this the g as in –g? Who knows?

19. So you want to add a .h file
Add the .h file to every .o file of a .cpp file that #includes the .h file, directly or indirectly.
runmaze.o : runmaze.cpp Maze.h SquareMaze.h MazeRunner.h RandomMazeRunner.h VisualizeSquareMazeRunner.h Fictitious.h
g++ -Wall -c -g runmaze.cpp
MazeRunner.o : MazeRunner.cpp Maze.h MazeRunner.h Fictitious.h
g++ -Wall -c -g MazeRunner.cpp
RandomMazeRunner.o : RandomMazeRunner.cpp Maze.h MazeRunner.h RandomMazeRunner.h
g++ -Wall -c -g RandomMazeRunner.cpp
But RandomMazeRunner.cpp doesn’t #include Fictitious.h
(in our example)

20. Adding a .cpp file
runmaze : runmaze.o MazeRunner.o RandomMazeRunner.o Maze.o SquareMaze.o VisualizeSquareMazeRunner.o GPKernel.o Bogus.o
g++ -o runmaze -g runmaze.o MazeRunner.o RandomMazeRunner.o Maze.o SquareMaze.o VisualizeSquareMazeRunner.o GPKernel.o Bogus.o -L/usr/X11R6/lib -lX11
Bogus.o : Bogus.cpp Bogus.h Maze.h MazeRunner.h
g++ -Wall -c -g Bogus.cpp
Add .o file to
dependencies of
executable program
Also, add .o file to
list of files to link
in (must do both)
Tell make how to
make Bogus.o

21. Debugging Recommendations:
Add print statements (or cout<<) so you can see what your program is doing.
Make them check a global variable (doDebug), so you can turn them off & on (make sure debugging is off before turning in your project).
Use gdb (see below)
Use xxgdb (has dinky graphical user interface)

22. start it/set a couple of breakpoints
break gdbSquareMaze::getStartMazeNode
is the form for putting a breakpoint on a C++ class method.

23. Run program in gdb To see more commands, the help command is help
or look at the extra information pointers near the beginning of these slides.

24. More info 326 Computing page (more info on these tools) GNU Info pages
GNU Info pages
Friendly people in lab / other students
man command