REGEX uses the Open Source Perl-Compatible Regular Expression (PCRE) library. Some form of this is typically already installed on most Unix systems, or can be acquired from http://www.pcre.org/. For Windows, it requires pcre.dll, which is included with A-Shell 5.1. For details on the syntax of regular expressions, see the Perl Regular Expression documentation.
PCRE is covered under the BSD license, which requires the following notes be included in the documentation included with A-Shell:
Written by: Philip Hazel
Email local part: ph10
Email domain: cam.ac.uk
University of Cambridge Computing Service, Cambridge, England.
Copyright (c) 1997-2020 University of Cambridge
All rights reserved.
This software is provided by the copyright holders and contributors "as is" and any express or implied warranties, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose are disclaimed. In no event shall the copyright owner or contributors be liable for any direct, indirect, incidental, special, exemplary, or consequential damages (including, but not limited to, procurement of substitute goods or services; loss of use, data, or profits; or business interruption) however caused and on any theory of liability, whether in contract, strict liability, or tort (including negligence or otherwise) arising in any way out of the use of this software, even if advised of the possibility of such damage.
