Actually, the assignment is not about Perl at all. Perl is just a convenient language to carry the assignment. The project is all about finding some vulnerabilities, in this case a race condition, and suggesting some solutions to avoid this vulnerability.
CountZero
A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James
My blog:
Imperial Deltronics