This new book by the world's leading programming language textbook authors carefully explains how to use Perl as a general-purpose programming language and how to program multi-tier, client/server, database-intensive, Internet-and-Web-based applications. Dr. Harvey M. Deitel and Paul J. Deitel are the principals of Deitel & Associates, Inc., the internationally recognized corporate training and content-creation organization specializing in C++, Javatrade;, C#, C, Visual Basicreg;, XMLtrade;, Python, Perl, Internet, World Wide Web and object technologies. The Deitels are also the authors of the world's #1 Java and C++ textbooks, Java How to Program, 3/e and C++ How to Program, 3/e. In Perl How to Program, the Deitels and their colleagues, Tem R. Nieto and David C. McPhie, discuss topics you need to build complete, Web-based applications including: CGI/HTML forms/XML/CGI.pm Control Structures/Arrays/Hashes Regular Expressions/Strings Objects/Encapsulation OOP/Inheritance/References Database/DBI/SQL/Signals/Contexts Security/Accessibility Typeglobs/File Globbing Networking/Sockts/Internet Protocols Cookies/Session Tracking Filehandles/Data Structures Process Control/Forking/Piping Subroutines/Modules/Packages/Overloading Web Automation/OLE Automation Server-Side Includes/Ties/Closures Graphics/GUI/Perl/TK Perl How to Program includes extensive pedagogic features: Hundreds of LIVE-CODEtrade; programs with screen captures that show exact outputs Extensive World Wide Web and Internet resources to encourage further research Hundreds of tips, recommended practices and cautions-all marked with icons

Dr. Harvey M. Deitel, CEO of Deitel & Associates, Inc., has 40 years in the computing field including extensive industry and academic experience. He is one of the world's leading computer science instructors and seminar presenters. Dr. Deitel earned B.S. and M.S. degrees from the Massachusetts Institute of Technology and a Ph.D. from Boston University. He has 20 years of college teaching experience including earning tenure and serving as the Chairman of the Computer Science Department at Boston College before founding Deitel & Associates, Inc. with his son Paul J. Deitel. He is author or co-author of several dozen books and multimedia packages and is currently writing many more. With translations published in Japanese, Russian, Spanish, Elementary Chinese, Advanced Chinese, Korean, French, Polish and Portuguese, Dr. Deitel's texts have earned international recognition. Dr. Deitel has delivered professional seminars internationally to major corporations, government organizations and various branches of the military.

Paul J. Deitel, Executive Vice President of Deitel & Associates, Inc., is a graduate of the Massachusetts Institute of Technology's Sloan School of Management where he studied Information Technology. Through Deitel & Associates, Inc. he has delivered Internet and World Wide Web courses and programming language classes for industry clients including Compaq, Sun Microsystems, White Sands Missile Range, Rogue Wave Software, Computervision, Straws, Fidelity, Cambridge Technology Partners, Lucent TecItnologies, Adra Systems, Entergy, CableData Systems, NASA at the Kennedy Space Center, the National Severe Storm Laboratory, IBM and many other organizations. He has lectured on for the Boston Chapter of the Association for Computing Machinery, and has taught satellite-based courses through a cooperative venture of Deitel & Associates, Inc., Prentice Hall and the Technology Education Network. He and his father, Dr. Harvey M. Deitel, are the world's best-selling Computer Science textbook authors.

Tem R. Nieto, Director of Product Development with Deitel & Associates, Inc., is a graduate of the Massachusetts Institute of Technology where he studied engineering and computing. Through Deitel & Associates, Inc. he has delivered courses for industry clients including Sun Microsystems, Compaq, EMC, Stratus, Fidelity, Art Technology, Progress Software, Toys "R" Us, Operational Support Facility of the National Oceanographic and Atmospheric Administration, Jet Propulsion Laboratory, Nynex, Motorola, Federal Reserve Bank of Chicago, Banyan, Schlumberger, University of Notre Dame, NASA, various military installations and many others. He has co-authored several books and multimedia packages with the Deitels and has contributed to virtually every Deitel & Associates, Inc. publication.

David Craig McPhie recently graduated from Harvard College magna cum laude with a B.A. in Physics, having completed extensive computer science course work in C, C++, Java and Lisp. His course work included a final project using CGI to implement an online word game ("Elggob") that won accolades from his instructors and peers. Prior to collaborating on Perl How to Program, David programmed a Monte Carlo electron path modeling application for AlliedSignal, Electron Vision Group in San Diego. His other computing experience includes software test script writing and implementation with SilkTest at Cakewalk Software, and debugging courtroom simulation software code at the Education Technology Department of Harvard Law School. David has now changed venues and is studying law at Harvard Law School. He maintains an interest in technology law, and continues to use Per in Web programming for student organizations. He and his wife Erin and daughter Emily live in Cambridge, MA.

PrefaceWelcome to Perl! This book is by an old guy and three young guys. The old guy (HMD; Massachusetts Institute of Technology 1967) has been programming and/or teaching programming for 40 years. The three young guys (PJD; MIT 1991, TRN; MIT 1992 and DCM Harvard 2000) have each been programming and/or teaching programming for many years. The old guy programs and teaches from experience; the young guys do so from an inexhaustible reserve of energy. The old guy wants clarity; the young guys want performance. The old guy seeks elegance and beauty; the young guys want results. We got together to produce a book we hope you will find informative, challenging and entertaining. Why We Wrote Perl How to ProgramDr. Harvey M. Deitel taught introductory programming courses in universities for 20 years with an emphasis on developing clearly written, well-designed programs. Much of what is taught in these courses is the basic principles of programming with an emphasis on the effective use of data types, control structures, arrays and functionalization. Our experience has been that students handle the material in this book in about the same manner as they handle it in introductory Pascal or C courses. There is one noticeable difference though: students are highly motivated by the fact that they are learning a leading-edge programming language and a leading-edge programming paradigm (object-based programming) that will be immediately useful to them as they leave the university environment and head into a world of e-business and e-commerce in which the Internet and the World Wide Web have a massive prominence.Our goal was clear: produce a textbook for introductory university-level courses in programming for students with little or no programming experience, yet offer the depth and the rigorous treatment of theory and practice demanded by traditional, upper-level programming courses to satisfy professionals' needs. To meet this goal, we produced a comprehensive book that patiently teaches the principles of control structures, object-based programming and Internet and World Wide Web programming in Perl. After mastering the material in this book, students will be well prepared to take advantage of the Internet and the Web as they take upper-level courses and venture into the rapidly changing business world.Perl How to Programis the ninth book in the Deitel/Prentice HallHow to Programseries. The key focus of this book is Web-based applications development. Our audiences want to build real-world, industrial-strength, Web-based applications. These audiences care about good looking Web pages. But they also care about client/server systems, databases and distributed computing.Many books about the Web are reference manuals with exhaustive listings of features. That is not our style. We concentrate on creating real applications. We provide the live-code examples on the CD accompanying this book so that you can run the applications and see the outputs.We are excited about the enormous range of possibilities the Internet and the Web offer. We performed extensive research for this book and located many Internet and Web resources (which we provide as live links on the CD-ROM that accompanies this book) to help you learn about Perl. These links include general information, tutorials and demonstrations.We have worked hard to create hundreds of useful live-code examples to help you master Perl programming quickly and effectively. All of the code examples are on the accompanying disk and are available for free download from our Web sites: www.deitel.com www.prenhall.com/deitelThe book's exercises range from simple recall questions to lengthy programming problems to major projects. Instructors requiring substantial term projects will find many appropriate problems listed in the exercises, especially in the la