CSCI 3294 (Unix Power Tools), Spring 2008:
Homework 6

Assigned:

March 3, 2008.

Due:

March 10, 2008, at 5pm.

Credit:

20 points.

Reading

Read about the following topics in the list of suggested readings, either in one of the suggested readings or in another book or reference. (This is the topic for March 3):

• The make utility.

Programming Problems

Do the following (sort-of-)programming problem. Turn in your finished makefile by sending mail to bmassing@cs.trinity.edu, with the file as an attachment. Please use a subject line that mentions the course number and the assignment (e.g., ``csci 3294 homework 6''). You can do this assignment on any system that provides the needed functionality, but I will check it on one of the department's Fedora 7 Linux machines, so you should probably make sure it works in that environment before turning it in.

1. (20 points) Suppose you have a C program consisting of the following files:
   • some-defs.h containing macro and constant definitions.
   • foo.h containing constants and prototype definitions for function foo.
   • foo.c containing code for function foo. This file contains #include directives to include some-defs.h and foo.h.
   • bar.h containing constants and prototype definitions for function bar.
   • bar.c containing code for function bar. This file contains #include directives to include some-defs.h and bar.h.
   • main.c containing code for the main program, which calls functions foo and bar. This file also contains #include directives to include some-defs.h, foo.h, and bar.h.

   Write a makefile that:

   • When you type make main, creates executable main from the source files, compiling just the parts of this program that need to be recompiled (because either source code has changed or an #include'd file has changed). Compile using any C compiler (cc or gcc) but using the flags -Wall, -pedantic, and -O.

   • When you type make clean, deletes all the object files for the program.

   • When you type make xclean, deletes all the object files for the program and the executable.

   You can make use of the implicit rules defined by make if they will help. (They probably will.) Here are some test files you can use to test your makefile:

   • some-defs.h
   • foo.h
   • foo.c
   • bar.h
   • bar.c
   • main.c

   Remember that the command touch can be used to change a file's timestamp without opening it in an editor, etc.