ActivePerl Developer’s Guide has three main focus areas. The first is to help programmers already familiar with Perl under Unix to migrate to the new platform. There are differences between the platforms, both from an architecture and supported function point of view. This book should help you bridge the gap from Perl programming to Windows programming, either by providing a Perl workaround, or by giving you the Windows-specific alternative.The second focus area is on developing applications with the ActivePerl development system. ActivePerl is the version of Perl produced by ActiveState which is already compiled and optimized for the Windows platform. ActivePerl is supplied as an installable application, thereby overcoming the biggest hurdle, that of compiling Perl on the Windows platform. ActivePerl also provides us with some features not offered in the standard Perl, including an extensive Windows specific library, a Perl Package Manager (similar to the CPAN module) and some neat abilities that help you develop Perl based web sites on Windows servers.The last focus area concentrates on helping people already familiar with programming Windows using Visual Basic and provides a guide for migrating their programming skills from VB to Perl.What this book is not is a tutorial guide to programming with Perl under Windows, or a complete reference to Perl for Windows programmers ­ many of the Perl functions and library are ignored if there are no differences between Unix and Windows implementations. Furthermore, it’s not a complete guide to applications development ­ we won’t be covering algorithms, or providing solutions to your development problems.We will, on the other hand, provide you with all the information you should ever need to enable you to develop applications using ActivePerl and the Win32 specific Perl libraries. Armed with that information, and providing you have an existing understanding about how to program with Perl, then you should be able to produce any application you like using this book and ActivePerl.Who Is the Book For?The target audience is directly split into two groups ­ existing Unix Perl programmers who need to develop a Windows specific or compatible application, and Visual Basic programmers who want to learn how to program in Perl.If you are in the former category, you’ll need to know Perl to a reasonable level already. The book is not a tutorial guide (although the last section may help). We’ve made the assumption that you already know how to program in Perl and know the basic operations and development processes behind writing a Perl script.For Visual Basic programmers, you’ll need to be well versed in VB, but not necessarily an expert. The last section gives a quick introduction to the Perl language, so providing you know how to program you should be able to pick up the Perl language quite quickly.How to Use This BookIf you are a Unix programmer, I suggest you use it as a reference in combination with another guide, such as Perl: The Complete Reference, to enable you to program in Perl under Windows. You should be able to find everything you need for successfully migrating your Unix Perl applications to Windows. If there’s something missing, let me know, and I’ll see what I can do.For Visual Basic programmers, skip to the last section, which gives an outline and overview of the differences, and then follows with a number of different aspects that are different between the two languages. Armed with this information, and the function migration guide in Appendix C, you should be up and running as a Perl programmer in no time at all.