NOTE: ALPHA AND BETA RELEASES OF TCL/TK ARE NOT SUPPORTED! -------------------- Introduction -------------------- This is the README file for Expect, a program that performs programmed dialogue with other interactive programs. It is briefly described by its man page, expect(1). This directory contains the source and man page for Expect. This README file covers Expect 5.38 and up. These versions of Expect work with Tcl 8.2 and up and Tk 8.2 and up. Significant changes and other news can be found in the NEWS file. The Expect home page is: http://expect.nist.gov The Expect FAQ is: http://expect.nist.gov/FAQ.html -------------------- Getting Started - The Preferable Way -------------------- A book on Expect is available from O'Reilly with the title "Exploring Expect: A Tcl-Based Toolkit for Automating Interactive Applications", ISBN 1-56592-090-2. The book is filled with detailed examples and explanations, and is a comprehensive tutorial to Expect. The book also includes a tutorial on Tcl written specifically for Expect users (so you don't have to read the Expect papers or the man pages). Exploring Expect is 602 pages. -------------------- Getting Started - The Hacker Way -------------------- While the book is the best way to learn about Expect, it is not absolutely necessary. There are man pages after all and there are numerous articles and papers on Expect. All of my own papers are in the public domain and can be received free. If you are a hacker on a tight budget, this may appeal to you. Nonetheless, I think you will find the book pays for itself very quickly. It is much more readable than the man pages, it includes well-written and explained examples, and it describes everything in the papers as a coherent whole. The concepts in the papers actually only make up a small fraction of the book. The 1990 USENIX paper (see "Readings" below) is probably the best one for understanding Expect conceptually. The 1991 Computing Systems and the LISA IV papers provide a nice mix of examples. The only downside is, the examples in these papers don't actually work anymore - some aspects (e.g., syntax) of both Expect and Tcl have changed. The papers still make interesting reading - just don't study the examples too closely! Fortunately, most of the examples from the papers also accompany this distribution - and all of these are up to date. For all the details, read the man page. It is long but you can get started just by skimming the sections on the following commands: spawn (starts a process) send (sends to a process) expect (waits for output from a process) interact (lets you interact with a process) To print out the Expect man page, invoke your local troff using the -man macros, such as either of: ptroff -man expect.man ditroff -man expect.man If Expect is installed, you can read the man pages using the "usual" man commands, such as "man expect". If not installed, view the man page on your screen by saying something like: nroff -man expect.man | more Expect uses Tcl as the underlying language for expressing things such as procedures, loops, file I/O, and arithmetic expressions. For many simple scripts, it is not necessary to learn about Tcl. Just by studying the examples, you will learn enough Tcl to get by. But if you would like to learn more about Tcl or use it in your own applications, read the Tcl README file which provides pointers to the extensive Tcl documentation. Or read Exploring Expect. Chapter 2 of Exploring Expect is a Tcl tutorial specifically designed for Expect users. An interactive debugger is bundled with Expect. The debugger has its own documentation that comes separately. It is listed in the Readings below. Again, it is slightly out of date. An up-to-date description of the debugger appears in Chapter 18 of Exploring Expect. This chapter also contains additional advice and tips for debugging. You may get the feeling that the Expect documentation is somewhat scattered and disorganized. This was true prior to publication of Exploring Expect. The book contains everything you need to know, all up-to-date, and with examples of every concept. (The book contains no references to any of the Expect papers because none are necessary.) ---------------------- Examples ---------------------- This distribution contains many example scripts. (All of the substantive examples in the book are included.) They can be found in the example directory of this distribution. The README file in that directory briefly describes all of the example scripts. Many of the more sophisticated examples have man pages of their own. Other interesting scripts are available separately in the directory http://expect.nist.gov/scripts/ (ftpable as ftp://ftp.nist.gov/mel/div826/subject/expect/scripts). (See below for how to retrieve these.) You are welcome to send me scripts to add to this directory. A number of Expect scripts are also available in the Tcl archive, available at ftp://ftp.neosoft.com/pub/tcl. -------------------- Readings on Expect -------------------- The implementation, philosophy, and design are discussed in "expect: Curing Those Uncontrollable Fits of Interaction", Proceedings of the Summer 1990 USENIX Conference, Anaheim, CA, June 11-15, 1990. Examples and discussion, specifically aimed at system administrators, are in "Using expect to Automate System Administration Tasks", Proceedings of the 1990 USENIX Large Systems Administration Conference (LISA) IV, Colorado Springs, CO, October 17-19, 1990. A comprehensive paper of example scripts is "expect: Scripts for Controlling Interactive Programs", Computing Systems, Vol. 4, No. 2, University of California Press Journals, 1991. Regression and conformance testing is discussed in "Regression Testing and Conformance Testing Interactive Programs", Proceedings of the Summer 1992 USENIX Conference, San Antonio, TX, June 8-12, 1992. An explanation of some of the more interesting source code to an early version of Expect is in Chapter 36 ("Expect") of "Obfuscated C and Other Mysteries", John Wiley & Sons, ISBN 0-471-57805-3, January 1993. A paper on connecting multiple interactive programs together using Expect is "Kibitz - Connecting Multiple Interactive Programs Together", Software - Practice & Experience, Vol. 23, No. 5, May 1993. The debugger is discussed in "A Debugger for Tcl Applications", Proceedings of the 1993 Tcl/Tk Workshop, Berkeley, CA, June 10-11, 1993. Using Expect with Tk is described in the paper "X Wrappers for Non-Graphic Interactive Programs", Proceedings of Xhibition '94, San Jose, CA, June 20-24, 1994. Simple techniques to allow secure handling of passwords in background processes are covered in "Handling Passwords with Security and Reliability in Background Processes", Proceedings of the 1994 USENIX LISA VIII Conference, San Diego, CA, September 19-23, 1994. More publications can be found in the Expect home page (see elsewhere). -------------------- How to Get the Latest Version of Expect or the Readings -------------------- Expect may be ftp'd as mel/div826/subject/expect/expect.tar.gz from expect.nist.gov. (Yes, the URL is much shorter: http://expect.nist.gov/expect.tar.Z) Request email delivery by mailing to "firstname.lastname@example.org". The contents of the message should be (no subject line) "send pub/expect/expect.tar.Z". Once you have retrieved the system, read the INSTALL file. The papers mentioned above can be retrieved separately (from the same directories listed above) as: doc/seminal.ps.Z (USENIX '90 - Intro and Implementation) doc/sysadm.ps.Z (LISA '90 - System Administration) doc/scripts.ps.Z (Comp. Systems '91 - Overview of Scripts) doc/regress.ps.Z (USENIX '92 - Testing) doc/kibitz.ps.Z (SP&E '93 - Automating Multiple Interactive Programs Simultaneously) doc/tcl-debug.ps.Z (Tcl/Tk '93 - Tcl/Tk Debugger) doc/expectk.ps.Z (Xhibition '94 - Using Expect with Tk) doc/bgpasswd.ps.Z (LISA '94 - Passwds in Background Procs) doc/chargraph.ps.Z (SP&E '96 - Testing and Automation of Character Graphic Applications) The book "Exploring Expect" is described in more detail earlier in this file. The book "Obfuscated C and Other Mysteries" is not on-line but is available in bookstores or directly from the publisher (Wiley). Overhead transparencies I've used at conferences are also available in the same way as the papers themselves. The transparencies are sketchy and not meant for personal education - however if you are familiar with Expect and just want to give a short talk on it to your colleagues, you may find the transparencies useful. They vary in length from 15 to 20 minutes in length. These are: doc/seminal-talk.ps.Z (USENIX '90 - Intro and Implementation) doc/sysadm-talk.ps.Z (LISA '90 - System Administration) doc/regress-talk.ps.Z (USENIX '92 - Testing) doc/tcl-debug-talk.ps.Z (Tcl/Tk '93 - Tcl/Tk Debugger) doc/expectk-talk.ps.Z (Xhibition '94 - Expect + Tk = Expectk) doc/bgpasswd-talk.ps.Z (LISA '94 - Passwords in the Background) All of the documents are compressed PostScript files and should be uncompressed and sent to a PostScript printer. The documents are intended for printing at 8.5"x11" and may fail on some ISO A4 printers. According to Hans Mayer <Hans.Mayer@gmd.de>, you can make them A4-able by searching for "FMVERSION" and changing the next line from: 1 1 0 0 612 792 0 1 13 FMDOCUMENT to: 1 1 0 0 594 841 0 1 13 FMDOCUMENT -------------------- Using Expect with and without Tcl and/or Tk. -------------------- The usual way of using Expect is as a standalone program with Tcl as the control language. Since you may already have Tcl, it is available separately. Tcl may be retrieved as tcl.tar.Z in the same way as described above for Expect. When new releases of Tcl appear, I will try to check them out for Expect as soon as possible. If you would like to get the newest Tcl release without waiting, ftp it from ftp.scriptics.com (directory pub/tcl). Expect may also be built using the Tk library, a Tcl interface to the X Window System. Tk is available in the same way as Tcl. It is possible to embed the Expect/Tcl core and optionally Tk in your own C programs. This is described in libexpect(3). Expect can also be used from a C or C++ program without Tcl. This is described in libexpect(3). While I consider this library to be easy to use, the standalone Expect program is much, much easier to use than working with the C compiler and its usual edit, compile, debug cycle. Unlike typical programming, most of the debugging isn't getting the C compiler to accept your programs - rather, it is getting the dialogue correct. Also, translating scripts from Expect to C is usually not necessary. For example, the speed of interactive dialogues is virtually never an issue. So please try 'expect' first. It is a more appropriate tool than the library for most people. -------------------- Systems Supported -------------------- I do not know of any UNIX systems on which Expect will not run. Systems which do not support select or poll can use Expect, but without the ability to run multiple processes simultaneously. I am willing to work with you to complete a port. Before sending me changes, please download or verify that you have the latest version of Expect (see above). Then send me a "diff -c" along with a suitable English explanation. If your diff involves something specific to a machine, give me diffs for configure.in as well or give me a hint about when the diffs should be done so I can write the configure support myself. Also please include the version of the OS and whether it is beta, current, recent, or totally out-of-date and unsupported. -------------------- Installing Expect -------------------- Expect comes with a configure script that provides for an automated installation. I believe you will find that Expect is very easy to install. (Tcl and Tk, too.) For more information, read the INSTALL file. -------------------- Support from Don Libes or NIST -------------------- Although I can't promise anything in the way of support, I'd be interested to hear about your experiences using it (good or bad). I'm also interested in hearing bug reports and suggestions for improvement even though I can't promise to implement them. If you send me a bug, fix, or question, include the version of Expect (as reported by expect -d), version of Tcl, and name and version of the OS that you are using. Before sending mail, it may be helpful to verify that your problem still exists in the latest version. You can check on the current release and whether it addresses your problems by retrieving the latest HISTORY file (see "History" above). Awards, love letters, and bug reports may be sent to: Don Libes National Institute of Standards and Technology Bldg 220, Rm A-127 Gaithersburg, MD 20899 (301) 975-3535 email@example.com I hereby place this software in the public domain. NIST and I would appreciate credit if this program or parts of it are used. Design and implementation of this program was funded primarily by myself. Funding contributors include the NIST Automated Manufacturing Research Facility (funded by the Navy Manufacturing Technology Program), the NIST Scientific and Technical Research Services, the ARPA Persistent Object Bases project and the Computer-aided Acquisition and the Logistic Support (CALS) program of the Office of the Secretary of Defense. Especially signicant contributions were made by John Ousterhout, Henry Spencer, and Rob Savoye. See the HISTORY file for others. -------------------- Commercial Support, Classes -------------------- Several companies provide commercial support for Expect. If your company has a financial investment in Expect or you wish to be assured of continuing support for Expect, you can buy a support contract this way. These companies currently include: ActiveState #200 - 580 Granville St Vancouver, BC V6C 1W6 Canada +1 (604) 484-6800 http://www.activestate.com/Company/contact.plex Cygnus Support 1937 Landings Drive Mountain View, CA 94043 +1 (415) 903-1400 firstname.lastname@example.org http://www.cygnus.com Computerized Processes Unlimited (CPU) 4200 S. I-10 Service Rd., Suite 205 Metairie, LA 70006 +1 (504) 889-2784 email@example.com http://www.cpu.com http://www.cpu.com/cpu/expect.htm (Expect class page) CPU provides Expect support and also Expect classes. Contact them for more information. Neither NIST nor I have any financial relationship with these companies. Please contact me to be added to this list.