Perl: The Complete Reference

1249 Pages·2001·8.207 MB·English

by  Martin C. Brown

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Perl: The Complete Reference
Second Edition
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Perl:
The Complete Reference
Second Edition
Martin C. Brown
Osborne/McGraw-Hill
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DOI: 10.1036/0072194251
To Darcy and Leon, two little kittens
who do try to help daddy with the typing,
but usually just end up typing
“jjskdjjvoookko000000000000000000000”
About the Author
Martin C. Brownis the author of six Perl
books, including the first edition ofPerl: The
Complete Reference,Perl Programmer’s Reference,
ActivePerl Developer’s Guide, andDebugging
Perl.In addition to Perl, he has worked in
Python,Java,VisualBasic,andotherlanguages.
A programmer for 15 years, he is the former
ITdirectorofalargeadvertisingagency
dealingwithbluechipclientssuchasHewlett
Packard, Oracle, and Cable & Wireless.
Copyright 2001 The McGraw-Hill Companies, Inc. Click Here for Terms of Use.
Contents at a Glance
Part I Fundamentals
1 Perl Backgrounder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2 Perl Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
3 Perl Parsing Rules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
4 Variables and Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
5 Statements and Control Structures . . . . . . . . . . . . . . . . . . 109
6 Subroutines, Packages, and Modules . . . . . . . . . . . . . . . . 123
7 Working with Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161
8 Data Manipulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209
9 Errors and Trapping Them . . . . . . . . . . . . . . . . . . . . . . . . . 269
Part II Programming with Perl
10 Complex Data Structures . . . . . . . . . . . . . . . . . . . . . . . . . . 287
11 System Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 339
12 Networking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 361
vii
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viii Perl: The Complete Reference
13 Database Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 391
14 Interprocess Communication . . . . . . . . . . . . . . . . . . . . . . . 447
15 Other Execution Enhancements . . . . . . . . . . . . . . . . . . . . . 479
Part III Developing Applications
16 User Interface Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 513
17 Advanced User Interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . 529
18 Developing for the World Wide Web (WWW) . . . . . . . . 575
19 Controlling Execution with Pragmas . . . . . . . . . . . . . . . . 611
20 Extending and Embedding Perl . . . . . . . . . . . . . . . . . . . . . 641
Part IV Fine-Tuning Applications
21 Debugging and Tuning . . . . . . . . . . . . . . . . . . . . . . . . . . . . 715
22 Perl Compiler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 773
23 Perl Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 803
24 Cross-Platform Migration Traps . . . . . . . . . . . . . . . . . . . . 825
25 Distributing Modules and Applications . . . . . . . . . . . . . . 837
Part V Appendixes
A Function Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 869
B Standard Perl Library . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 993
C Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1141
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1153
Contents
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxxiii
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxxv
Part I
Fundamentals
1 Perl Backgrounder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Versions and Naming Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Perl, perl or PeRl? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Life Before Perl 5.6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Perl History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Main Perl Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Perl Is Free . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Perl Is Simple to Learn, Concise, and Easy to Read . . . . . . 7
Perl Is Fast . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Perl Is Extensible . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Perl Has Flexible Data Types . . . . . . . . . . . . . . . . . . . . . . . . . 8
Perl Is Object Oriented . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Perl Is Collaborative . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Compiler or Interpreter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
ix
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