1 `chem' is a `roff' language to generate chemical structure diagrams.
2 `@g@chem' is a `groff' preprocessor that produces output suitable for
3 the `@g@pic' preprocessor.
5 The original version of `chem' is an `awk' script written by Brian
6 Kernighan <http://cm.bell-labs.com/cm/cs/who/bwk/index.html>. The
7 source files of the `awk' version of `chem' are available at
8 <http://cm.bell-labs.com/netlib/typesetting/chem.gz>.
10 This project is a rewrite of `chem' in Perl for the GNU `roff' project
11 `groff'. It was written under Perl v5.8.8, but at least Perl v5.6 is
12 needed to run the Perl version of `chem'.
14 In comparison to the original `awk' version of `chem', the Perl
15 version does the following changements:
16 - the options -h, --help, -v, --version to output usage and version
17 information are added.
18 - remove some functions `inline', `shiftfields', and `set' and some
19 variables that are used only once.
21 The subdirectory `examples/' contains example files for chem. They
22 are written in the `chem' language. The file names end with .chem.
27 Copyright (C) 2006-2014 Free Software Foundation, Inc.
28 Written by Bernd Warken <groff-bernd.warken-72@web.de>.
30 This file is part of `chem', which is part of `groff'.
32 `groff' is free software; you can redistribute it and/or modify it
33 under the terms of the GNU General Public License (GPL) vbersion 2 as
34 published by the Free Software Foundation.
36 `groff' is distributed in the hope that it will be useful, but WITHOUT
37 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
38 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
41 The GPL2 license text is available in the internet at
42 <http://www.gnu.org/licenses/gpl-2.0.html>.
45 ####### Emacs settings