Exploring Expect

Using Expect In Commercial Applications—Legalese

It is not necessary to license Expect. Most of Expect is in the public domain, but two parts of it have copyrights. The Tcl core and the regular expression engine inside Expect are copyrighted but otherwise freely available, allowing the software to be used for any purpose and without fee, and with few restrictions on the code other than maintaining the copyright internally. The full copyright notices follow:

• Copyright (c) 1987-1993 The Regents of the University of California. All rights reserved.

• Permission is hereby granted, without written agreement and without license or royalty fees, to use, copy, modify, and distribute this software and its documentation for any purpose, provided that the above copyright notice and the following two paragraphs appear in all copies of this software.

• In no event shall the University of California be liable to any party for direct, indirect, special, incidental, or consequential damages arising out of the use of this software and its documentation, even if the University of California has been advised of the possibility of such damage.

• The University of California specifically disclaims any warranties, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose. The software provided hereunder is on an “as is” basis, and the University of California has no obligation to provide maintenance, support, updates, enhancements, or modifications.

• Copyright (c) 1986 by University of Toronto. Written by Henry Spencer. Not derived from licensed software.

• Permission is granted to anyone to use this software for any purpose on any computer system, and to redistribute it freely, subject to the following restrictions:

  1. The author is not responsible for the consequences of use of this software, no matter how awful, even if they arise from defects in it.

  2. The origin of this software must not be misrepresented, either by explicit claim or by omission.

  3. Altered versions must be plainly marked as such, and must not be misrepresented as being the original software.

The following notice is required on the NIST-authored portions of Expect:

• This software was produced by the National Institute of Standards and Technology (NIST), an agency of the U.S. government, and by statute is not subject to copyright in the United States. Recipients of this software assume all responsibility associated with its operation, modification, maintenance, and subsequent redistribution.

So you can use Expect in other freely-redistributable or commercial packages. You can even use pieces of the code in other software products. Just don’t blame the authors for any problems encountered with the software.