CS 444/544 Programming Project 1

CS 444/544 Programming Project 1
Submit a single gzipped tar file to TEACH. The
single gzipped tar file should contain the all source files (C
source [*.c and *.h] and the Makefile). Submitting your
solutions before October 2nd will earn you a 10% bonus. You
must have a single Makefile to build all portions of this
assignment. If you don’t know how to create a gzipped tar
file, you need to learn before you submit this assignment.
This assignment should be an easy refresher for you. it is not
intended to be a long arduous assignment.
1. Create a single Makefile that will build all of the below C programs. Place them all in a single
directory (no sub-directories). If you don’t have a Makefile, your submission will not be graded. If
your Makefile does not build a portion of your assignment, that portion will receive a zero grade.
I expect to build all the programs below by using the following two commands:
make clean
make all
If this does not work, it will be bad for your grade on this assignment.
2. Write a C program that calls fork(). Before calling fork(), have the parent process assign the
value 100 to int called xx. What value is the value of xx in the child process? Have the parent
process assign the value 999 to xx and have the child process assign the value 777 to xx. What
happens to xx variable when both the child and parent change the value of xx? Have both
processes print the value of xx.
3. Write a C program that opens a file name “JUNK.txt” (with the fopen() function call). Have
the parent process print “before fork” into the file. The parent process should call fork() to
create a new process. Have the parent process perform a for loop that prints “parent” into the
open file 10 times. Have the child process perform a for loop that prints “child” into the open file
10 times. What happens when they are writing to the file concurrently, i.e., at the same time
(answer this in the comments in your code)?
4. Write a C program using fork(). The child process should print “hello” to stdout; the parent
process should print “goodbye” to stdout. Make sure that the child process always prints first.
Can you do this without the parent calling wait() in the parent (and NOT using some big loop in
the parent)?
5. Write a C program that calls fork() and then the child process calls each of the following exec()
functions to run the program “ls -l -F -h”: execl(), execlp(), execv(), and
execvp(). The parent process must wait until the child process is complete before it exits.
Describe the differences of the exec functions in your code as comments.
Final note
The programming projects in this course are intended to give you basic skills. In later programming
projects, we will assume that you have mastered the skills introduced in earlier programming projects. If
you don’t understand, ask questions.