This library is licensed under the GNU LGPL with linking exception---this is the most used license for Free Pascal libraries and allows you to use this library within your own applications. You do not need to use the GNU LGPL on your whole application (but it would be great) but only on this library.
There is one exception to this. The file src/flqueue.pas comes under the Mozilla Public License or the GNU General Public License.
This library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version with the following modification:
As a special exception, the copyright holders of this library give you permission to link this library with independent modules to produce an executable, regardless of the license terms of these independent modules,and to copy and distribute the resulting executable under terms of your choice, provided that you also meet, for each linked independent module, the terms and conditions of the license of that module. An independent module is a module which is not derived from or based on this library. If you modify this library, you may extend this exception to your version of the library, but you are not obligated to do so. If you do not wish to do so, delete this exception statement from your version.
See file COPYING.LGPL.txt for full license text.
All files included in the subdirectory test are test and demo programs. You may use them freely for learning purposes or as an hint on how to create your own applications.