Logistics

  • Due: Monday, March 31st AoE.
  • Submission instructions: make sure that the required files (main.c, planet.c, planet.h, and Makefile) are in your csci112_spring2025/classwork/week12/mon/ directory.
  • Deadline reminder: after the deadline passes, you cannot earn any points for this assignment.

Learning outcomes

  • Practice writing a Makefile

Assignment

  • Log in to the server.
  • From your home directory, navigate to /csci112_spring2025/classwork/week12/mon/, creating directories week12 and mon if necessary.
  • Copy the main.c, planet.c, and planet.h file from /public/classwork/week12/mon to your directory.

Now, write a Makefile to compile main.c and planet.c into one executable program, a.out. Your Makefile should also encode the correct dependencies for the program, which are the following:

  • a.out depends on object files main.o and planet.o compiled from main.c and planet.c
  • main.o depends on main.c and planet.h
  • planet.o depends on planet.c and planet.h

Running make should only recompile code that has changed. (Or code that depends on code that has changed.) For example, here is a sample sequences of calls to make after files get “changed” using touch:

[g73x595@csci112 mon]$ ls
main.c  Makefile  planet.c  planet.h
[g73x595@csci112 mon]$ make
gcc -c main.c -Wall
gcc -c planet.c -Wall
gcc main.o planet.o -Wall
[g73x595@csci112 mon]$ ls
a.out  main.c  main.o  Makefile  planet.c  planet.h  planet.o
[g73x595@csci112 mon]$ ./a.out
Enter a planet name, diameter, num. moons, orbit time, and rotation time: Mars 6779.0 2 1.88 24.61
Enter a planet name, diameter, num. moons, orbit time, and rotation time: Earth 12756.0 1 1.0 24.0
Jupiter: 142800 diameter, 16 moons, 11.90 orbit time, 9.93 rot. time
Mars: 6779 diameter, 2 moons, 1.88 orbit time, 24.61 rot. time
Earth: 12756 diameter, 1 moons, 1.00 orbit time, 24.00 rot. time
[g73x595@csci112 mon]$ touch planet.h
[g73x595@csci112 mon]$ make
gcc -c main.c -Wall
gcc -c planet.c -Wall
gcc main.o planet.o -Wall
[g73x595@csci112 mon]$ touch main.c
[g73x595@csci112 mon]$ make
gcc -c main.c -Wall
gcc main.o planet.o -Wall
[g73x595@csci112 mon]$ touch planet.o
[g73x595@csci112 mon]$ make
gcc main.o planet.o -Wall
[g73x595@csci112 mon]$ make
make: 'a.out' is up to date.

Autograder

You can run the autograder by running

/public/classwork/week12/mon/autograder.sh

The file autograder.txt will be created with your score.

Grading turnaround

The autograder will be run at 6am to calculate final scores. Scores will be uploaded to D2L by the next class period.