John K. Ousterhout - Tcl and the Tk Toolkit

Brian W. Kernighan, Consulting Editor

Matthew H. Austern, Generic Programming and the STL: Using and Extending the C++ Standard Template Library

David R. Butenhof, Programming with POSIXThreads

Brent Callaghan, NFS Illustrated

Tom Cargill, C++ Programming Style

William R. Cheswick/Steven M. Bellovin/Aviel D. Rubin, Firewalls and Internet Security, Second Edition: Repelling the Wily Hacker

David A. Curry, UNIXSystem Security: A Guide for Users and System Administrators

Stephen C. Dewhurst, C++ Gotchas: Avoiding Common Problems in Coding and Design

Dan Farmer/Wietse Venema, Forensic Discovery

Erich Gamma/Richard Helm/Ralph Johnson/John Vlissides, Design Patterns: Elements of Reusable Object-Oriented Software

Erich Gamma/Richard Helm/Ralph Johnson/John Vlissides, Design Patterns CD: Elements of Reusable Object-Oriented Software

Peter Haggar, Practical JavaProgramming Language Guide

David R. Hanson, C Interfaces and Implementations: Techniques for Creating Reusable Software

Mark Harrison/Michael McLennan, Effective Tcl/Tk Programming: Writing Better Programs with Tcl and Tk

Michi Henning/Steve Vinoski, Advanced CORBAProgramming with C++

Brian W. Kernighan/Rob Pike, The Practice of Programming

S. Keshav, An Engineering Approach to Computer Networking: ATM Networks, the Internet, and the Telephone Network

John Lakos, Large-Scale C++ Software Design

Scott Meyers, Effective C++ CD: 85 Specific Ways to Improve Your Programs and Designs

Scott Meyers, Effective C++, Third Edition: 55 Specific Ways to Improve Your Programs and Designs

Scott Meyers, More Effective C++: 35 New Ways to Improve Your Programs and Designs

Scott Meyers, Effective STL: 50 Specific Ways to Improve Your Use of the Standard Template Library

Robert B. Murray, C++ Strategies and Tactics

David R. Musser/Gillmer J. Derge/Atul Saini, STL Tutorial and Reference Guide, Second Edition: C++ Programming with the Standard Template Library

John K. Ousterhout, Tcl and the Tk Toolkit

Craig Partridge, Gigabit Networking

Radia Perlman, Interconnections, Second Edition: Bridges, Routers, Switches, and Internetworking Protocols

Stephen A. Rago, UNIXSystem V Network Programming

Eric S. Raymond, The Art of UNIX Programming

Marc J. Rochkind, Advanced UNIX Programming, Second Edition

Curt Schimmel, UNIXSystems for Modern Architectures: Symmetric Multiprocessing and Caching for Kernel Programmers

W. Richard Stevens, TCP/IP Illustrated, Volume 1: The Protocols

W. Richard Stevens, TCP/IP Illustrated, Volume 3: TCP for Transactions, HTTP, NNTP, and the UNIXDomain Protocols

W. Richard Stevens/Bill Fenner/Andrew M. Rudoff, UNIX Network Programming Volume 1, Third Edition: The Sockets Networking API

W. Richard Stevens/Stephen A. Rago, Advanced Programming in the UNIXEnvironment, Second Edition

W. Richard Stevens/Gary R. Wright, TCP/IP Illustrated Volumes 1-3 Boxed Set

John Viega/Gary McGraw, Building Secure Software: How to Avoid Security Problems the Right Way

Gary R. Wright/W. Richard Stevens, TCP/IP Illustrated, Volume 2: The Implementation

Ruixi Yuan/W. Timothy Strayer, Virtual Private Networks: Technologies and Solutions

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Library of Congress Cataloging-in-Publication Data

Ousterhout, John K.
Tcl and the Tk toolkit / John Ousterhout, Ken Jones ; with contributions by
Eric Foster-Johnson... [et al.]. 2nd ed.
p. cm.
Includes index.
ISBN 978-0-321-33633-0 (pbk. : alk. paper)
1. Tcl (Computer program language) 2. Tk toolkit. I. Jones, Ken. II. Title.
QA76.73.T44O97 2009
005.13'3dc22
2009022005

Copyright 2010 Pearson Education, Inc.

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Fax: (617) 671-3447

ISBN-13: 978-0-321-33633-0
ISBN-10: 0-321-33633-X
Text printed in the United States on recycled paper at Edwards Brothers in Ann Arbor, Michigan.
First printing, August 2009

Tcl and Tk have evolved tremendously since John wrote the first edition of this book. In a History of Tcl that John wrote several years ago ( http://www.tcl.tk/about/history.html ), he documented several significant enhancements that occurred:

I joined Sun in May of 1994 and began building a team of Tcl developers... The additional resources provided by Sun allowed us to make major improvements to Tcl and Tk. Scott Stanton and Ray Johnson ported Tcl and Tk to Windows and the Macintosh, so that Tcl became an outstanding cross-platform development environment... Jacob Levy and Scott Stanton overhauled the I/O system and added socket support, so that Tcl could easily be used for a variety of network applications. Brian Lewis built a bytecode compiler for Tcl scripts, which provided speedups of as much as a factor of 10x. Jacob Levy implemented Safe-Tcl, a powerful security model that allows untrusted scripts to be evaluated safely. Jacob Levy and Laurent Demailly built a Tcl plugin, so that Tcl scripts can be evaluated in a web browser, and we created Jacl and TclBlend, which allow Tcl and Java to work closely together. We added many other smaller improvements, such as dynamic loading, namespaces, time and date support, binary I/O, additional file manipulation commands, and an improved font mechanism.