CGI Programming Unleashe

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C  O  N  T  E  N  T  S

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Chapter 1  What CGI Programs Can and Can't Do

• What CGI Is Useful For
  • Simple Tasks
  • Intermediate Tasks
  • Advanced Tasks
• What CGI Is Not Useful For
• What CGI Programs Can Do
  • What CGI Can't Do
• Summary

Chapter 2  The CGI Specification

• CGI Overview
• Languages
• CGI Methods
  • GET Method
  • POST Method
  • HEAD Method
• Interface Specification
  • Environment Variables
  • Command Line
  • Standard Input
  • Standard Output
• Examples
• More Information
• Summary

Chapter 3  Crash Course in CGI

• Why CGI Exists
• Wanna Have a Conversation?
  • Making a Connection
  • Getting Down to Business
• Parlez Vous Environment Variables?
  • Server-Specific Environment Variables
  • Client-Specific Environment Variables
  • Request-Specific Environment Variables
• Taking It All In
  • REQUEST_METHOD
  • Strange Looking Data
• RSVP
  • Types of Responses
  • Headers
• Some Things to Consider
• Summary

Chapter 4  Comparison of the Various CGI Programming Libraries

• CGI Libraries for C Programming
  • CGIc 1.05
  • CGI-HTML 1.21
• The C++ CGI Class Libraries
  • AHTML
  • Kelly Black's CGI C++ Classes
• Perl Libraries
  • CGI-Lib
• Summary

Chapter 5  Designing Your CGI Application

• Sizing It Up
  • What Does the Application Have to Do?
  • Preliminary Sketches
• Scoping It Out
  • Pseudocode
  • Planning for Processing
  • Gathering Input
  • Processing
  • Generating Output
• The Fine Print
  • Libraries
  • Languages
  • Share with Your Neighbors
  • Planning for the Future
• You Can Take It with You
  • Server Software
  • Operating Systems
  • Reuse
• Summary

Chapter 6  Testing and Debugging

• The Process and Methodology
  • The Review Cycle
  • At Your Command…
• Solitary Confinement
  • Preventing Harm to Original Data
  • Is Not Easily Accessible to General Users
• Ladies and Gentlemen, Start Your Testing
• • The Testing Process
• Debugging the Application
  • Common Errors
  • Make Use of Error Logs
  • Debugging Flags
  • Re-Testing Your Application
• Summary

Chapter 7  Server-Side Includes (SSI) and Gateway

• What Are Server-Side Includes, and What Are They Useful For?
• Comparison of SSI and CGIs
• Which Servers Support SSI?
  • Cern
  • Apache
• A List of Useful SSI Directives
• Some SSI Examples
  • Counter
  • Random Image Generator
• The Protocol of the Web: HTTP
• Gateways: Accessing Other Protocols through the Web
• Improving Existing Gateways
• Some Gateway Examples
  • finger
  • Form-by-Mail
• Using the Web as a Standard Internet Access Interface
• Summary

Chapter 8  Forms and How to Handle Them

• What Is an HTML Form?
  • What Can Forms Do?
  • What Can't Forms Do?
• Creating HTML Forms
  • A Sample HTML Form
  • HTML Form Tags
  • INPUT TYPE=TEXT
  • INPUT TYPE=SUBMIT
  • INPUT TYPE=RESET
  • INPUT TYPE=RADIO
  • INPUT TYPE=chECKBOX
  • INPUT TYPE=IMAGE
  • INPUT TYPE=HIDDEN
  • TEXTAREA
  • SELECT
  • Future FORM HTML Tags Proposed in the "Draft HTML 3.0 Spec"
  • Form Style
  • A Sample Form
• Handling Form Submissions
  • REQUEST_TYPEs GET versus POST
  • Form Data Decoding
  • Choosing the Programming Language
  • A Sample CGI Form Handler Program
  • Forms-Based Intranet/Internet Client/Server Applications
• Forms Ready Reference
  • Brief Outline of GET and POST Mechanisms
  • Brief Outline of Form Encoding
• Summary

Chapter 9  Security

• Is CGI Insecure?
  • CGI Is a Power Tool-Use with Care
  • General Internet Security Issues
  • Alternatives to CGI
  • Can CGI Be Used Securely?
• Security Is the Responsibility of Both Programmer and Administrator
• • What Can a Web Server Administrator Do to Improve Security?
  • What Can a CGI Programmer Do to Improve Security?
• Summary

Chapter 10  Databases

• Database Interfaces
  • Front End CGIs
• Web Indexing
  • Indexers
  • Search Engines
• Large Scale Databases
• Summary

Chapter 11  Searching and CGI

• Searching Information on the Web
• Most Important Search Engines
• Gathering Information on the Internet
• Searching Interfaces for the Final User
• CGI Work in the Background
• Developing a Simple CGI for a White Pages Database
• Future Improvements
• Summary

Chapter 12  Imagemaps

• Imagemaps-Myth, Metaphor, and Meaning
• Anatomy of an Image-Pixels and Coordinates
• HTML, ISMAP, and QUERY_STRING- Passing Imagemap Information to a CGI Program
• Flatland Revisited-An Introduction to the Standard Imagemap System
  • Imagemap.c-The Standard Imagemap Handler
  • .map Files-Describing Shapes the Imagemap Way
• Client-Side Imagemaps and Magic MIME Types
  • Client-Side Imagemaps
  • The .map Magic MIME Type
• Take a Walk on the Server-Side-Developing Imagemap Code
• Creative Imagemap Programming-Breaking the Paradigm with Glorglox
• Imagebuttons-The End of Imagemaps Is Nigh
  • The HTML Side of Imagebuttons
  • But What Does It All Mean?
• Summary

Chapter 13  Proprietary Extensions to Servers

• Server Push
• HTTP Cookies
• Other Server Extensions
  • WebServer/400
  • Apache Modules
  • Jigsaw Resources
  • Netscape and Microsoft
• Summary

Chapter 14  WinCGI The Basics

• Your Very First WinCGI Program
• Authentication
• Summary

Chapter 15  Windows CGI: Database Backending

• Database and Data Formats
  • Flat File Database
  • Relational Database
• Communicating with Databases
  • Flat File Read
  • ODBC
  • SQL
  • DDE
• Database Tools
  • Visual Basic
  • Delphi
  • C/C++
  • Other Tools
• Creating Your Database
  • The Data
  • The Tools
  • Communications
  • The Code
  • Using the Database
• Summary

Chapter 16  DOS CGI: The Basics

• The Basics
  • CONTENT_FILE
  • OUTPUT_FILE
  • Other Environment Variables
• Languages
  • BAT and CMD Files
  • BASIC and Its Cousins
  • Perl for DOS
  • C/C++
• Limitations
• Resources
  • Converting Other CGI Programs and Information
  • Web Server Software
  • DOS Programming Books
• Summary

Chapter 17  Voting Booths

• Voting Booths-Gathering and Managing Opinions
• Starting Simple-A Low-Level Voting Booth
• Bad Voting Booth, Good Code-Technical Merits of greenegg.cgi
  • Use of Associative Arrays for the Handling of GET/POST Method Data
  • Immediate Error Trapping Using the Statement Modifier Form of if
  • Slurping Data with @array = <FILEHANDLE>;
  • Use of Output Filter to Provide stdin to /usr/sbin/sendmail and sendmail -t Flag
  • Use of print FH<<END; ... END Syntax When Outputting Formatted Sections
• A Voting Booth Wish List
• Multistate CGI Programs-More Than Just a URL
• Generating Meaningful Reports
  • Sorting Lists in Perl
  • Average and Standard Deviation-Statistics 101
  • Visual Output-Creating Graphs
  • Handling Data Internally and Externally
• Summary

Chapter 18  Discussion Forums

• Discussion Forums-Everything Old Is New Again
• Discussion Forum Display and Bistate CGI Programming
• Useful Data Fields for Discussion Forums and Parent/Sibling/Child Relationships
• A Discussion Forum Example
• Discussion Forum Administration
  • Remove Posting by Date
  • Remove Thread by Date
  • Remove Posting by Author
  • Remove Individual Postings
  • Remove Individual Threads
• Discussion Forum Additions
• Selective Sorting Criteria
• Search Engines
• Registered Users and .htaccess Schemes
• Summary

Chapter 19  Chat Rooms

• Chat Rooms-Getting a Life on the Internet
• Prescription for a Chat Room
• Getting chat.cgi to Work for You
• Chat Room Systems and Entry Pages
• Extension to the Basic Chat Room
• Intelligent User Identification
• ChatMaster-The Chat Room Administrator
• Private Messaging
  • Other Chat Room Features and Examples
• Alternatives to CGI Chat Rooms
  • IRC-Internet Relay Chat
  • PowWow
  • Java Chat Rooms
  • talk and ytalk-Old UNIX Standbys
  • MUD, MUSH, and MOO Systems
• Summary

Chapter 20  Multi-User Games and CGI

• Multi-User Games
  • Planning
  • Outlining
  • Coding
• Summary

Chapter 21  Tracking Users

• Why Do We Need to Track Users?
• The Essence of Web Marketing
• Parsing Access Logs
  • What Is an Access Log?
• Environment Variables
• Creating a Pseudo Access Log File
• Logging Accesses
• How to Implement Tracking CGIs
  • index.cgi
  • index.shtml
  • Including CGIs in Images
• A Simple Web Counter
• Calling counter.cgi
• Locating Users Geographically
  • Discussion of Feasibility
  • Introduction to NSLOOKUP and WHOIS
  • Limitations of Tracking Users Through IP Addresses
• Cookies
• Other Methods of Tracking Users
  • Fingering Dial-Up Servers
• The Ethics of Tracking Users
• Accessing This Chapter Online
• Summary

Chapter 22  Simple Order Entry

• What This Chapter Covers

• Forms and the Data They Produce
  • The FORM Tag
  • Methods
  • Environment Variables
  • What the Raw Data Looks Like
• Processing the Data with Perl
  • A Simple Parsing CGI
  • The Output of the Simple CGI
  • Parsing the Data: Round 2
  • Accepting Forms by METHOD=GET
• Checking for Errors
  • Embedding Information in the Form
  • What to Do with All This Data?
  • The Things You Keep
• Security Issues
  • Transaction Security
  • CGI Security
• Summary

Chapter 23  Shopping Carts

• What Are Shopping Cart CGIs?
• What This Chapter Covers
• The Basic Elements of a Shopping Cart CGI
  • The Product Catalog
  • Using Hidden Input Fields to Maintain State
• Other Ways of Keeping Track of State
• • htaccess and REMOTE_USER
  • Session ID Embedding
  • HTTP Cookies
  • Cookie Recipes
  • Setting Cookies with <META HTTP-equiv>
  • Building Customer Profiles
• Database Management
  • Using DBMs
• The Result of Your Labors, cart.cgi
• Summary

Chapter 24  Java and JavaScript Alternatives to CGI

• Java: Bringing More Dynamics to the Web
• What Is JavaScript?
• Differences between Java and JavaScript
• Comparison of CGI and Java/JavaScript
• Communication between Java and CGI
• Java to CGI
• CGI to Java
• Java and JavaScript
• JavaScript
• Each Technique Has Its Place
• Future Improvements
• Where to Get More Information
• Summary

Chapter 25  ISAPI

• What Is ISAPI All About?
• ISAPI Background and Functionality
  • Internet Server Applications (ISAs)
  • Internet Server API Filter
  • Implementation Complications
• Summary

Chapter 26  NSAPI

• Why NSAPI?
• NSAPI versus CGI
  • Performance
  • Process Space
  • Data and Function Access
• NSAPI and the Server's Processes
  • HTTP Request/Response Process
  • Server Application Functions
  • Controlling Function Use
• Functions and Features
  • Server Application Function Prototype
  • Parameter Blocks
  • Sessions
  • Request Structure
  • Functions, Variables, and Their Responses
• Implementation Considerations
  • Cross-Platform Capabilities
  • Informational Resources
  • Programming Knowledge
  • Debugging
• The Future of the NSAPI
• Summary

Chapter 27  ActiveXControls

• ActiveX Concepts and Background
  • OLE and COM
  • "Containers" for Anything
  • ActiveX, Son of OLE
  • Component Categories
• Why They Matter
  • Functionality
  • Financials
• ActiveX Controls in Action
  • ActiveMovie
  • HTML Layout Control
  • Other Controls
• Developing ActiveX Controls
  • Underlying Programming Basics
  • Control Framework
  • Tools for Creation
• Integrating Controls with Your Web Site
  • The <OBJECT> tag
  • Internet Component Download
• ActiveX Viability and Directions
  • Who's Going to Develop?
  • Opening the Standard?
  • Going Cross Platform
  • Competitive Standards
  • Netscape and ActiveX
  • Market
• Resources
  • ActiveX SDK
  • OLE and OCX Controls Books
  • Web Sites
  • Existing Developers (Visual Basic and C++)
• Summary

Chapter 28  ActiveX Scripting

• Blending HTML and Programming
• • Script Tag
  • Interface Components
• The ActiveX Scripting Model
  • IE 3.0 Browser Object Model
  • ActiveX Controls and Components
  • VBScript Objects
• The Languages
  • JavaScript
  • VBScript
• Scripting Hosts and Engines
  • Hosts
  • Engines
• Resources
  • Going from VB to VBScript
  • VBScript Language and Runtime References
  • Web Sites

Summary

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