This page describes Expect and that can be found at this site. First, Expect . . .
Introduction
Expect is a tool for automating interactive applications such as
telnet, ftp, passwd, fsck, rlogin, tip, etc. Expect really makes this
stuff trivial. Expect is also useful for testing these same
applications. And by adding Tk, you can also wrap interactive
applications in X11 GUIs.
Expect can make easy all sorts of tasks that are prohibitively
difficult with anything else. You will find that Expect is an
absolutely invaluable tool - using it, you will be able to automate
tasks that you've never even thought of before - and you'll be able to
do this automation quickly and easily.
Ok - enough of the hype. More information on Expect is
available in the following documents:
- Download or
now!
- is
the book on Expect.
-
-
-
- is the same README file that comes with
Expect. The README has lots of valuable information that has yet to
be incorporated into this home page. It includes a description of the
software distribution, where and how to send bug reports, how to get
support or classes, and some other background information.
- History about the development of Expect and differences between versions. The current version of Expect is
5.43.0, created Mon Feb 07 09:19:54 PM EST 2005.
or .
The gz file is preferrable simply because it is quicker to download.
However, if you have no idea what to do with a gz file once you've got
it, just transfer the Z version of the distribution. Then, at the
command line, type:
uncompress expect.tar.Z
tar -xvf expect.tar
This will create a directory containing the Expect distribution.
Change to that directory and read the README file.
Note: Expect requires Tcl. If you don't already have Tcl, you
can download it as source from the Tcl Developer Xchange web site or as binaries from ActiveState.
The most current snapshots of Expect will be found in the CVS repository. Not all
snapshots are official releases.
Not all old versions of Expect are available, but . The current version is also available this way if you need to refer to it by explicit version.
The md5 hash for expect.tar.gz (also available by explicit version as ) is: 230400129630335b3060a42f66fec11d
| Author |
Location |
Other notes |
|
|
Native port, based on Expect V5.39 and Tcl 8.4+, runs on XP/NT/2k. Available with support or as part of ASPN Tcl. |
|
|
Native port, based on Expect V5.21 |
|
|
A cygwin-based port (i.e., feels like UNIX), version unknown, bundled with DejaGnus |
The distribution contains many example scripts, including
well-known scripts such as multixterm, kibitz, rftp (recursive ftp), passmass,
autoexpect and the delicious beer script. All of the substantive
examples in the book are included and many of them have man pages
themselves. Here's the .
The best way to obtain the examples is to follow the directions for
obtaining Expect (above). Once you have received and unpacked the distribution, you
can find the examples in the example directory. You can also retrieve examples, man pages, and web pages
although you run the risk of trying an example that depends on a more
up-to-date version of Expect than you have installed. (The web pages
were all generated from the man pages so there should be no difference
in content.)
Here are man pages for some of the examples. (Not all of the examples need man pages but these do.)
[The following statement is required per NIST policy] By
selecting these links, you will be leaving NIST webspace. We have
provided these links to other web sites because they may have
information that would be of interest to you. No inferences should be
drawn on account of other sites being referenced, or not, from this
page. There may be other web sites that are more appropriate for your
purpose. NIST does not necessarily endorse the views expressed, or
concur with the facts presented on these sites. Further, NIST does not
endorse any commercial products that may be mentioned on these sites.
The following are some other particularly worthwhile Expect-related
links.
-
is a popular Expect-based framework for testing other programs. If
you are starting out and feel overwhelmed by the capabilities of
Expect or would just like some guidance on how to structure a test
suite, check out DejaGnu. DejaGnu is used by many standards testing
organizations.
-
is a rapid prototyping, development and delivery
environment for GUI-based applications on Unix platforms. WINTERP uses
Lisp instead of Tcl.
- is the Expect library embedded in Python instead of Tcl.
- is a true
compiler for Tcl/Tk. It also includes support for Expect.
"Exploring Expect" is an excellent resource for learning and
using Expect. (Pub: O'Reilly, ISBN 1-56592-090-2) The book contains
hundreds of examples and also includes a tutorial on Tcl. Exploring
Expect is 602 pages.
NIST policy is to avoid endorsements for commercial products or
organizations. Hence this page provides no link for the publisher
or any further information about how to obtain the book.
Articles, Papers, and Chapters on Expect
- Fisher, David L., , November, 1999.
- Libes, D., "Expect", Tcl/Tk Extensions, ed, Mark Harrison, O'Reilly
& Associates, Inc., 1997.
- Libes, D.,
"Writing a Tcl Extension in Only ... 7 Years" (,
),
,
Proceedings of the
Fifth Annual Tcl/Tk Workshop '97, Boston, MA, July 14-7, 1997.
Winner of Best Paper Award at conference.
- Libes, D., "", , John Wiley & Sons, West Sussex,
England, to appear. [This paper isn't really about Expect per se.
However, a large section of the paper is on tknewsbiff which is one of
the Expect examples.]
- Friesenhahn, B., "Expect Offers UNIX Scripting", , April 1997.
- Libes, D., , , Vol. 27(2), p 123-137,
February 1997.
- Libes, D., "How to Avoid Learning
Expect -- or -- Automating Automating Interactive Programs" (, ),
Proceedings of the Tenth USENIX System Administration Conference (LISA
X), Chicago, IL, September 30 - October 4, 1996.
- Libes, D., "Writing CGI Scripts in Tcl" (, ), Proceedings
of the Fourth Annual Tcl/Tk Workshop '96, Monterey, CA, July 10-13,
1996. [This paper isn't really about Expect per se. However, it does
show a nice example of Expect in a CGI script for the purpose of
changing passwords through web pages. The complete form/script can be
found in the source distribution.] Winner of Best Presentation
Award at conference.
- Libes, D., , Proceedings of The 21st Annual Trenton Computer
Festival (TCF '96), Trenton, NJ, April 21-22, 1996 - a much longer and
more detailed version of the SP&E paper (above) [I submitted this
originally to SP&E and they cut it down to what ultimately appeared but
recommended that this version was still worth publishing elsewhere -
hence this second publication.]
- Faught, D., Testing Interactive Programs, Software QA
Magazine, Vol. 3, No. 1, February 1996.
- Fischer, P., The Expect Program
and Other Skunkware Tools, SCO World, February, 1996.
- Libes, D., Handling
Passwords with Security and Reliability in Background Processes
(,
),
Proceedings of the 1994 USENIX LISA VIII Conference, San Diego, CA,
September 19-23, 1994 - Simple techniques to allow secure handling of
passwords in background processes.
- Morse, W., A Tcl/Tk and Expect Tutorial, World Wide
Technology Conference, Houston, TX, December 1, 1994. Winner of
Best Paper Award at conference.
- Libes, D., Ouch, Those Programs Are Painful, ORA.COM,
O'Reilly & Associates, Inc., Fall '94.
- Libes, D., , Proceedings of the 1993 Tcl/Tk
Workshop, Berkeley, CA, June 10-11, 1993 - A presentation of the Tcl
debugger - theory, implementation, and use.
Warning: The examples in all of the papers listed
below here are archaic. Critical aspects (usually syntax) of both
Expect and Tcl have changed since they were written. (It's not that
Expect has changed that recently - rather it's because of incredibly
slow turnaround by many reviewers, editors, and journals.)
The papers still make interesting reading - just don't study the
examples too closely! Fortunately, most of the examples from the
papers also accompany the Expect distribution - and all of the online
examples are up to date.
- McNutt, D., Expect, January, 1994,
UNIX Review, Vol. 12, No. 6, January 1994 - Introductory article.
- Libes, D., , Proceedings of Xhibition
'94, San Jose, CA, June 20-24, 1994 - Discussion of wrapping
interactive programs with Tk.
- Dichter, C., Surviving Software
Testing, UNIX Review, pps 29-36, V11, #2, Feb 1993.
- Libes, D., , Software -
Practice & Experience, Vol. 23, No. 5, May 1993 - Paper on connecting
multiple interactive programs together using Expect.
- Libes, D., , John Wiley & Sons, ISBN
0-471-57805-3, January 1993 - An explanation of some of the more
interesting source code to an early version of Expect.
- Libes, D., Automating Interactive Applications in the Network
Environment, International Communications Association Journal, May
17, 1992.
- Smith, B., Software Corner, Byte Magazine, 1992.
- Caffrey, P., User Interfaces and Automating Computer Human
Interaction, MSc. Thesis, Amdahl Ireland Ltd., 1992.
- Woodson, B., Regression Testing Using Expect, How To
Implement Quality In Software Conference, Santa Clara Valley Software
Quality Association, June 29, 1991.
- Libes, D., , Proceedings
of the Summer 1992 USENIX Conference, San Antonio, TX, June 8-12, 1992
- Discussion of regression and conformance testing. If you are
interested in this, you should also check out .
- Libes, D., , Computing Systems,
Vol. 4, No. 2, University of California Press Journals, 1991 - A nice
overview with a balance of example scripts and explanations.
- Libes, D., Implementor's
Notebook: Implementing a Trap Command, C Users Journal, Vol. 9,
No. 3, R&D Publications, Lawrence, KS, January, March, 1991 -
Explanation of how Expect's trap command was implemented.
- Libes, D., Implementor's
Notebook: Expect, C Users Journal, Vol. 9, No. 1, R&D
Publications, Lawrence, KS, January, January, 1991 - Explanation of
some of the more interesting source code to an early version of Expect
(an improved version of this appeared later as Obfuscated C and Other
Mysteries, Chapter 36 ("Expect").
- Anderson, D., "Expect", January, 1991, SunExpert Magazine,
Vol. 2, No. 1, January 1991 - Introductory article.
- Libes, D., , Proceedings of the 1990
USENIX Large Systems Administration Conference (LISA) IV, Colorado
Springs, CO, October 17-19, 1990 - Examples and discussion,
specifically aimed at system administrators.
- Libes, D., , Proceedings of
the Summer 1990 USENIX Conference, Anaheim, CA, June 11-15, 1990 -
Discussion of Expect's implementation, philosophy, and some
performance notes.
Expect was conceived of in September, 1987. The bulk of version 2 was
designed and written between January and April, 1990. Minor evolution
occurred after that until Tcl 6.0 was released. At that time
(October, 1991) approximately half of Expect was rewritten for version
3. See the
for more information. The HISTORY file is included with the Expect
distribution.
Around January 1993, an alpha version of Expect 4 was introduced.
This included Tk support as well as a large number of enhancements. A
few changes were made to the user interface itself, which is why the
major version number was changed. A production version of Expect 4
was released in August 1993.
In October 1993, an alpha version of Expect 5 was released to match
Tcl 7.0. A large number of enhancements were made, including some
changes to the user interface itself, which is why the major version
number was changed (again). The production version of Expect 5 was
released in March '94.
In the summer of 1999, substantial rewriting of Expect was done in order
to support Tcl 8.2. (Expect was never ported to 8.1 as it contained
fundamental deficiencies.) This included the creation of an exp-channel
driver and object support in order to take advantage of the new regexp
engine and UTF/Unicode. The user interface is highly but not entirely
backward compatible. See the NEWS file in the distribution for more detail.
There are important differences between Expect 3, 4, and 5. See the
CHANGES.* files in the distribution if you want to read about the
differences. Expect 5.30 and earlier versions have ceased development
and are not supported. However, the old code is available from
The Expect book became available in January '95. It describes Expect
5 as it is today, rather than how Expect 5 was when it was originally
released. Thus, if you have not upgraded Expect since before getting
the book, you should upgrade now.
Historical notes on Tcl and Tk according to John Ousterhout
I got the idea for Tcl while on sabbatical leave at DEC's
Western Research Laboratory in the fall of 1987. I started actually
implementing it when I got back to Berkeley in the spring of 1988; by
summer of that year it was in use in some internal applications of
ours, but there was no Tk. The first external releases of Tcl were in
1989, I believe. I started implementing Tk in 1989, and the first
release of Tk was in 1991.
- - A service to allow
collaborative management of identifiers.
-
- A comprehensive library for creating Tcl-based CGI scripts. cgi.tcl
supports tables, cookies, file upload, Expect, Tcl applets, Java, etc,
etc.
-
- A Tcl debugger. Provides traditional debugging capabilities to any
Tcl script. Built in to Expect but it works with any Tcl extension
including Tk. Can be dynamically loaded.
- - allows
arbitrary commands (play audio clip, metamail, etc) to be executed
upon mail reception. (If you like xbiff++ but wish it were more
flexible or more portable, then you'll like tkbiff.) tkbiff is
flexible enough that you can make it do anything. Default behavior:
fast and convenient access to new email using very little screen real
estate.
- and
- Computes
md5 and sha1 message digests using only core Tcl commands. Surprisingly fast.
(Surprised me anyway.)
- - A very easy-to-use FAQ builder. Simplifies maintenance
of hyperlinks, automatically repeats the questions with links to the
answers, automatically produces different formats (currently only text
and html supported), etc.
- - A
little stopwatch - just right for helping you get the timing down
while practicing a talk. Provided both as an applet and a standalone
Tk script.
Even more links
[The following statement is required per NIST policy] By
selecting these links, you will be leaving NIST webspace. We have
provided these links to other web sites because they may have
information that would be of interest to you. No inferences should be
drawn on account of other sites being referenced, or not, from this
page. There may be other web sites that are more appropriate for your
purpose. NIST does not necessarily endorse the views expressed, or
concur with the facts presented on these sites. Further, NIST does not
endorse any commercial products that may be mentioned on these sites.
The following links have nothing specifically to do with Expect
but may be significant in their value to Expect users nonetheless:
Books
- Tcl and the Tk Toolkit by John Ousterhout, Addison-Wesley, 1994,
ISBN 0-201-63337-X - the seminal book on Tcl and Tk.
- by Brent Welch, Prentice Hall, 1995, ISBN
0-13-182007-9.
- by Eric F. Johnson, M&T Books, 1996,
ISBN 1-55851-471-6 - Covers cross-platform development with Tcl and Tk
on Windows and UNIX.
- There are too many books to list all of them here. See the Tcl
FAQ for a bigger list.
FAQs
Miscellaneous
Pages that are particularly worthwhile but don't fall in the preceding
categories.
Last edited: Tue Feb 8 16:45:38 EST 2005
Technical Contact:
