Perl in a Nutshell, 2nd Edition

Chapter 20. The LWP Library

The library for web access in Perl (LWP), is a bundle of modules that provide a consistent, object-oriented approach to creating web applications. The library, downloaded as the single file named libwww-perl, contains the following classes :

File

Parses directory listings.

Font

Handles Adobe Font Metrics.

HTML

Parses HTML files and converts them to printable or other forms.

HTTP

Provides client requests, server responses, and protocol implementation.

LWP

The core of all web client programs. It creates network connections and manages the communication and transactions between client and server.

URI

Creates, parses, and translates URLs.

WWW

Implements standards used for robots (automatic client programs).

Each module in LWP provides different building blocks that allow you to do basically anything you can do in a Web browser—from connection, to request, to response and returned data. These parts are then encapsulated by an object to give a standard interface to every web program you write.

This chapter covers all the modules in the LWP distribution. While some modules are more useful than others, everything you need to know about LWP is included here. To begin with, the following section gives an overview of how LWP works to create a web client.