Perl Cookbook

The Perl Cookbook is a comprehensive collection of problems, solutions, and practical examplesfor anyone programming in Perl. Topics range from beginner questions to techniques that even the most experienced Perl programmer can learn from. More than just a collection of tips and tricks, the Perl Cookbook is the long-awaited companion volume to Programming Perl, filled with previously unpublished Perl arcana.

The Perl Cookbook contains thousands of examples ranging from brief one-liners to complete applications. Covered topic areas include:

• Manipulation of strings, numbers, dates, arrays, and hashes
• Reading, writing, and updating text and binary files
• Pattern matching and text substitutions
• Subroutines, libraries, and modules
• References, data structures, objects, and classes
• Signals and exceptions
• Accessing text, hashes, and SQL databases
• Screen addressing, menus, and graphical applications
• Managing other processes
• Writing secure scripts
• Client-server programming
• Internet applications programming with mail, news, FTP, and telnet
• CGI programming and web automation

These recipes were rigorously reviewed by score of the best minds inside and outside Perl, including Larry Wall, the creator of Perl.

1. Strings
0. Introduction
1. Accessing Substrings
2. Establishing a Default Value
3. Exchanging Values Without Using Temporary Variables
4. Converting Between ASCII Characters and Values
5. Processing a String One Character at a Time
6. Reversing a String by Word or Character
7. Expanding and Compressing Tabs
8. Expanding Variables in User Input
9. Controlling Case
10. Interpolating Functions and Expressions Within Strings
11. Indenting Here Documents
12. Reformatting Paragraphs
13. Escaping Characters
14. Trimming Blanks from the Ends of a String
15. Parsing Comma-Separated Data
16. Soundex Matching
17. Program: fixstyle
18. Program: psgrep
2. Numbers
0. Introduction
1. Checking Whether a String Is a Valid Number
2. Comparing Floating-Point Numbers
3. Rounding Floating-Point Numbers
4. Converting Between Binary and Decimal
5. Operating on a Series of Integers
6. Working with Roman Numerals
7. Generating Random Numbers
8. Generating Different Random Numbers
9. Making Numbers Even More Random
10. Generating Biased Random Numbers
11. Doing Trigonometry in Degrees, not Radians
12. Calculating More Trigonometric Functions
13. Taking Logarithms
14. Multiplying Matrices
15. Using Complex Numbers
16. Converting Between Octal and Hexadecimal
17. Putting Commas in Numbers
18. Printing Correct Plurals
19. Program: Calculating Prime Factors
3. Dates and Times
0. Introduction
1. Finding Today's Date
2. Converting DMYHMS to Epoch Seconds
3. Converting Epoch Seconds to DMYHMS
4. Adding to or subtracting from a Date
5. Difference of Two Dates
6. Day in a Week/Month/Year or Week Number
7. Parsing Dates and Times from Strings
8. Printing a Date
9. High-Resolution Timers
10. Short Sleeps
11. Program: hopdelta
4. Arrays
0. Introduction
1. Specifying a List In Your Program
2. Printing a List with Commas
3. Changing Array Size
4. Doing Something with Every Element in a List
5. Iterating Over an Array by Reference
6. Extracting Unique Elements from a List
7. Finding Elements in One Array but Not Another
8. Computing Union, Intersection, or Difference of Unique Lists
9. Appending One Array to Another
10. Reversing an Array
11. Processing Multiple Elements of an Array
12. Finding the First List Element That Passes a Test
13. Finding All Elements in an Array Matching Certain Criteria
14. Sorting an Array Numerically
15. Sorting a List by Computable Field
16. Implementing a Circular List
17. Randomizing an Array
18. Program: words
19. Program: permute
5. Hashes
0. Introduction
1. Adding an Element to a Hash
2. Testing for the Presence of a Key in a Hash
3. Deleting from a Hash
4. Traversing a Hash
5. Printing a Hash
6. Retrieving from a Hash in Insertion Order
7. Hashes with Multiple Values Per Key
8. Inverting a Hash
9. Sorting a Hash
10. Merging Hashes
11. Finding Common or Different Keys in Two Hashes
12. Hashing References
13. Presizing a Hash
14. Finding the Most Common Anything
15. Representing Relationships Between Data
16. Program: dutree
6. Pattern Matching
0. Introduction
1. Copying and Substituting Simultaneously
2. Matching Letters
3. Matching Words
4. Commenting regular Expressions
5. Finding the Nth Occurrence of a Match
6. Matching Multiple Lines
7. Reading Records with a Pattern Separator
8. Extracting a Range of Lines
9. Matching Shell Globs as Regular Expressions
10. Speeding Up Interpolated Matches
11. Testing for a valid Value
12. Honoring Locale Settings in Regular Expressions
13. Approximate Matching
14. Matching from Where the Last Pattern Left Off
15. Greedy and Non-Greedy Matches
16. Detecting Duplicate Words
17. Expressing AND, OR, and NOT in a Single Pattern
18. Matching Multiple-Byte Characters
19. Matching a Valid Mail Address
20. Matching Abbreviations
21. Program: urlify
22. Program: tcgrep
23. Regular Expression Grabbag
7. File Access
0. Introduction
1. Opening a File
2. Opening Files with Unusual Filenames
3. Expanding Tildes in Filenames
4. Making Perl Report Filenames in Errors
5. Creating Temporary Files
6. Storing Files Inside Your program Text
7. Writing a Filter
8. Modifying a File in Place with a Temporary File
9. Modifying a File in Place with -i Switch
10. Modifying a File in Place Without a Temporary File
11. Locking a File
12. Flushing Output
13. Reading from Many Filehandles Without Blocking
14. Doing Non-Blocking I/O
15. Determining the Number of Bytes to Read
16. Storing Filehandles in Variables
17. Caching Open Output Filehandles
18. Printing to Many Filehandles Simultaneously
19. Opening and Closing File Descriptors by Number
20. Copying Filehandles
21. Program: netlock
22. Program: lockarea
8. File Contents
0. Introduction
1. Reading Lines with Continuation Characters
2. Counting Lines (or Paragraphs or Records) in a File
3. Processing Every Word in a File
4. Reading a File Backwards by Line or Paragraph
5. Trailing a Growing File
6. Picking a Random Line from a File
7. Randomizing All Lines
8. Reading a Particular Line in a File
9. Processing Variable-Length Text Fields
10. Removing the Last Line of a File
11. Processing Binary Files
12. Using Random-Access I/O
13. Updating a Random-Access File
14. Reading a String from a Binary File
15. Reading Fixed-Length Records
16. Reading Configuration Files
17. Testing a File for Trustworthiness
18. Program: tailwtmp
19. Program: tctee
20. Program: laston
9. Directories
0. Introduction
1. Getting and Setting Timestamps
2. Deleting a File
3. Copying or Moving a File
4. Recognizing Two Names for the Same File
5. Processing All Files in a Directory
6. Globbing, or Getting a List of Filenames Matching a Pattern
7. Processing All Files in a Directory Recursively
8. Removing a Directory and Its Contents
9. Renaming Files
10. Splitting a Filename into Its Component Parts
11. Program: symirror
12. Program: lst
10. Subroutines
0. Introduction
1. Accessing Subroutine Arguments
2. Making Variables Private to a Function
3. Creating Persistent Private Variables
4. Determining Current Function Name
5. Passing Arrays and Hashes by Reference
6. Detecting Return Context
7. Passing by Named Parameter
8. Skipping Selected Return Values
9. Returning More Than One Array or Hash
10. Returning Failure
11. Prototyping Functions
12. Handling Exceptions
13. Saving Global Variables
14. Redefining a Function
15. Trapping Undefined Functioon Calls with AUTOLOAD
16. Nesting Subroutines
17. Program: Sorting Your Mail
11. References and Records
0. Introduction
1. Taking references to Arrays
2. Making Hashes of Arrays
3. Taking References to Hashes
4. Taking References to Functions
5. Taking References to Scalars
6. Creating Arrays of Scalar References
7. Using Closures Instead of Objects
8. Creating References to Methods
9. Constructing Records
10. Reading and Writing Hash Records to Text Files
11. Printing Data Structures
12. Copying Data Structures
13. Storing Data Structures to Disk
14. Transparently Persistent Data Structures
15. Program: Binary Trees
12. Packages, Libraries, and Modules
0. Introduction
1. Defining a Module's Interface
2. Trapping Errors in require or use
3. Delaying use Until Run Time
4. Making Variables Private to a Module
5. Determining the Caller's Package
6. Automating Module Clean-Up
7. Keeping Your Own Module Directory
8. Preparing a Module for Distribution
9. Speeding Module Loading with SelfLoader
10. Speeding Up Module Loading with Autoloader
11. Overriding Built-In Functions
12. Reporting Errors and Warnings Like Built-Ins
13. Referring to Packages Indirectly
14. Using h2ph to Translate C #include Files
15. Using h2xs to Make a Module with C Code
16. Documenting Your Module with Pod
17. Building and Installing a CPAN Module
18. Example: Module Template
19. Program: Finding Versions and Descriptions of Installed Modules
13. Classes, Objects, and Ties
0. Introduction
1. Constructing an Object
2. Destroying an Object
3. Managing Instance Data
4. Managing Class Data
5. Using Classes as Structs
6. Cloning Objects
7. Calling Methods Indirectly
8. Determining Subclass Membership
9. Writing an Inheritable Class
10. Accessing Overridden Methods
11. Generating Attribute Methods Using AUTOLOAD
12. Solving the Data Inheritance Problem
13. Coping with Circular Data Structures
14. Overloading Operators
15. Creating Magic Variables with tie
14. Database Access
0. Introduction
1. Making and Using a DBM File
2. Emptying a DBM File
3. Converting Between DBM Files
4. Merging DBM Files
5. Locking DBM Files
6. Sorting Large DBM Files
7. Treating a Text File as a Database Army
8. Storing Complex Data in a DBM File
9. Persistent Data
10. Executing an SQL Command Using DBI and DBD
11. Program: ggh — Grep Netscape Global History
15. User Interfaces
0. Introduction
1. Parsing Program Arguments
2. Testing Whether a Program Is Running Interactively
3. Clearing the Screen
4. Determining Terminal or Window Size
5. Changing Text Color
6. Reading from the Keyboard
7. Ringing the Terminal Bell
8. Using POSIX termios
9. Checking for Waiting Input
10. Reading Passwords
11. Editing Input
12. Managing the Screen
13. Controlling Another Program with Expect
14. Creating Menus with Tk
15. Creating Dialog Boxes with Tk
16. Responding to Tk Resize Events
17. Removing the DOS Shell Window with Windos Perl/Tk
18. Program: Small termcap program
19. Program: tkshufflepod
16. Process Management and Communication
0. Introduction
1. Gathering Output from a Program
2. Running Another Program
3. Replacing the Current Program with a Different One
4. Reading or Writing to Another Program
5. Filtering Your Own Output
6. Preprocessing Input
7. Reading STDERR from a Program
8. Controlling Input and Output of Another Program
9. Controlling the Input, Output, and Error of Another Program
10. Communicating Between Related Processes
11. Making a Process Look Like a File with Named Pipes
12. Sharing Variables in Different Processes
13. Listing Available Signals
14. Sending a Signal
15. Installing a Signal Handler
16. Temporarily Overriding a Signal Handler
17. Writing a Signal Handler
18. Catching Ctrl-C
19. Avoiding Zombie Processes
20. Blocking Signals
21. Timing Out an Operation
22. Program: sigrand
17. Sockets
0. Introduction
1. Writing a TCP Client
2. Writing a TCP Server
3. Communicating over TCP
4. Setting Up a UDP Client
5. Setting Up a UDP Server
6. Using UNIX Domain Sockets
7. Identifying the Other End of a Socket
8. Finding Your Own Name and Address
9. Closing a Socket After Forking
10. Writing Bidirectional Clients
11. Forking Servers
12. Pre-Forking Servers
13. Non-Forking Servers
14. Writing a Multi-Homed Server
15. Making a Daemon Server
16. Restarting a Server on Demand
17. Program: backsniff
18. Program: fwdport
18. Internet Services
0. Introduction
1. Simple DNS Lookups
2. Being an FTP Client
3. Sending Mail
4. Reading and Posting Usenet News Messages
5. Reading Mail with POP3
6. Simulating Telnet from a Program
7. Pinging a Machine
8. Using Whois to retrive Information from the InterNIC
9. Program: expn and vrfy
19. CGI Programming
0. Introduction
1. Writing a CGI Script
2. Redirecting Error Messages
3. Fixing a 500 Server Error
4. Writing a Safe CGI Program
5. Making CGI Scripts Efficient
6. Executing Commands Without Shell Escapes
7. Formatting Lists and Tables with HTML Shortcuts
8. Redirecting to a Different Location
9. Debugging the Raw HTTP Exchange
10. Managing Cookies
11. Creating Sticky Widgets
12. Writing a Multiscreen CGI Scripts
13. Saving a Form to a File or Mail Pipe
14. Program: chemiserie
20. Web Automation
0. Introduction
1. Fetching a URL from a Perl Script
2. Autmating Form Submission
3. Extracting URLs
4. Converting ASCII to HTML
5. Converting HTML to ASCII
6. Extracting or Removing HTML Tags
7. Finding Stale Links
8. Finding fresh Links
9. Creating HTML Templates
10. Mirroring Web Pages
11. Creating a Robot
12. Parsing a Web Server Log File
13. Processing Servers Logs
14. Program: htmlsub
15. Program: hrefsub

If you're into Perl, this is maybe OK. Otherwise, it doesn't add much to your knowledge.