Table Of Content,Title.7160 Page i Friday, August 18, 2006 8:18 AM
Programming Python
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,Title.7160 Page iii Friday, August 18, 2006 8:18 AM
THIRD EDITION
Programming Python
Mark Lutz
Beijing • Cambridge • Farnham • Köln • Paris • Sebastopol • Taipei • Tokyo
,Copyright.7029 Page iv Friday, August 18, 2006 8:17 AM
Programming Python, Third Edition
by Mark Lutz
Copyright © 2006, 2001, 1996 O’Reilly Media, Inc. All rights reserved.
Printed in the United States of America.
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no responsibility for errors or omissions, or for damages resulting from the use of the information
contained herein.
ISBN-10: 0-596-00925-9
ISBN-13: 978-0-596-00925-0
[M]
Table of Contents
Foreword. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .xiii
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxi
Part I. The Beginning
1. Introducing Python . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
“And Now for Something Completely Different” 3
Python Philosophy 101 3
The Life of Python 8
Signs of the Python Times 9
The Compulsory Features List 15
What’s Python Good For? 17
What’s Python Not Good For? 20
Truth in Advertising 22
2. A Sneak Preview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
“Programming Python: The Short Story” 24
The Task 24
Step 1: Representing Records 25
Step 2: Storing Records Persistently 35
Step 3: Stepping Up to OOP 47
Step 4: Adding Console Interaction 57
Step 5: Adding a GUI 60
Step 6: Adding a Web Interface 70
The End of the Demo 86
v
Part II. System Programming
3. System Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
“The os.path to Knowledge” 89
System Scripting Overview 90
Introducing the sys Module 100
Introducing the os Module 104
Script Execution Context 113
Current Working Directory 114
Command-Line Arguments 117
Shell Environment Variables 119
Standard Streams 123
4. File and Directory Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142
“Erase Your Hard Drive in Five Easy Steps!” 142
File Tools 142
Directory Tools 159
5. Parallel System Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
“Telling the Monkeys What to Do” 175
Forking Processes 176
Threads 183
Program Exits 201
Interprocess Communication 208
Pipes 209
Signals 218
Other Ways to Start Programs 221
A Portable Program-Launch Framework 230
Other System Tools 235
6. System Examples: Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236
“Splits and Joins and Alien Invasions” 236
Splitting and Joining Files 237
Generating Forward-Link Web Pages 247
A Regression Test Script 251
Packing and Unpacking Files 254
Automated Program Launchers 265
vi | Table of Contents
7. System Examples: Directories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 294
“The Greps of Wrath” 294
Fixing DOS Line Ends 294
Fixing DOS Filenames 307
Searching Directory Trees 311
Visitor: Walking Trees Generically 317
Copying Directory Trees 339
Deleting Directory Trees 345
Comparing Directory Trees 349
Part III. GUI Programming
8. Graphical User Interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 365
“Here’s Looking at You, Kid” 365
Python GUI Development Options 367
Tkinter Overview 371
Climbing the GUI Learning Curve 375
Tkinter Coding Basics 377
Tkinter Coding Alternatives 380
Adding Buttons and Callbacks 386
Adding User-Defined Callback Handlers 389
Adding Multiple Widgets 401
Customizing Widgets with Classes 406
Reusable GUI Components with Classes 408
The End of the Tutorial 414
Python/Tkinter for Tcl/Tk Converts 416
9. A Tkinter Tour, Part 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 418
“Widgets and Gadgets and GUIs, Oh My!” 418
Configuring Widget Appearance 419
Top-Level Windows 422
Dialogs 427
Binding Events 443
Message and Entry 448
Checkbutton, Radiobutton, and Scale 456
Running GUI Code Three Ways 468
Images 478
Viewing and Processing Images with PIL 483
Table of Contents | vii
10. A Tkinter Tour, Part 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 499
“On Today’s Menu: Spam, Spam, and Spam” 499
Menus 499
Listboxes and Scrollbars 511
Text 517
Canvas 529
Grids 543
Time Tools, Threads, and Animation 559
The End of the Tour 570
The PyDemos and PyGadgets Launchers 571
11. GUI Coding Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 583
“Building a Better Mouse Trap” 583
GuiMixin: Common Tool Mixin Classes 584
GuiMaker: Automating Menus and Toolbars 586
ShellGui: GUIs for Command-Line Tools 597
GuiStreams: Redirecting Streams to Widgets 605
Reloading Callback Handlers Dynamically 609
Wrapping Up Top-Level Window Interfaces 611
GUIs, Threads, and Queues 616
More Ways to Add GUIs to Non-GUI Code 624
12. Complete GUI Programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 636
“Python, Open Source, and Camaros” 636
PyEdit: A Text Editor Program/Object 638
PyPhoto: An Image Viewer and Resizer 657
PyView: An Image and Notes Slideshow 668
PyDraw: Painting and Moving Graphics 676
PyClock: An Analog/Digital Clock Widget 685
PyToe: A Tic-Tac-Toe Game Widget 700
Where to Go from Here 704
Part IV. Internet Programming
13. Network Scripting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 709
“Tune In, Log On, and Drop Out” 709
Plumbing the Internet 713
Socket Programming 720
viii | Table of Contents
