License

The Crystal Project are released under LGPL.

GNU General Public License.

   0. This License Agreement applies to any software library or other program
      which contains a notice placed by the copyright holder or other
      authorized party saying it may be distributed under the terms of this
      Lesser General Public License (also called "this License"). Each
      licensee is addressed as "you".

      A "library" means a collection of software functions and/or data
      prepared so as to be conveniently linked with application programs
      (which use some of those functions and data) to form executables.

      The "Library", below, refers to any such software library or work which
      has been distributed under these terms. A "work based on the Library"
      means either the Library or any derivative work under copyright law:
      that is to say, a work containing the Library or a portion of it,
      either verbatim or with modifications and/or translated
      straightforwardly into another language. (Hereinafter, translation is
      included without limitation in the term "modification".)

      "Source code" for a work means the preferred form of the work for
      making modifications to it. For a library, complete source code means
      all the source code for all modules it contains, plus any associated
      interface definition files, plus the scripts used to control
      compilation and installation of the library.

      Activities other than copying, distribution and modification are not
      covered by this License; they are outside its scope. The act of running a
      program using the Library is not restricted, and output from such a
      program is covered only if its contents constitute a work based on the
      Library (independent  of the use of the Library in a tool for writing
      it). Whether that is true depends on what the Library does and what the
      program that uses the Library does. 


   1. You may copy and distribute verbatim copies of the Library's complete
      source code as you receive it, in any medium, provided that you
      conspicuously and appropriately publish on each copy an appropriate
      copyright notice and disclaimer of warranty; keep intact all the notices
      that refer to this License and to the absence of any warranty; and
      distribute a copy of this License along with the Library.

      You may charge a fee for the physical act of transferring a copy, and
      you may at your option offer warranty protection in exchange for a fee.


   2. You may modify your copy or copies of the Library or any portion of it,
      thus forming a work based on the Library, and copy and distribute such
      modifications or work under the terms of Section 1 above, provided that
      you also meet all of these conditions:

         a. The modified work must itself be a software library.

         b. You must cause the files modified to carry prominent notices
            stating that you changed the files and the date of any change. 

         c. You must cause the whole of the work to be licensed at no charge
            to all third parties under the terms of this License.

         d. If a facility in the modified Library refers to a function or a
            table of data to be supplied by an application program that uses the
            facility, other than as an argument passed when the facility is
	    invoked, then you must make a good faith effort to ensure that, in
            the event an application does not supply such function or table,
            the facility still operates, and performs whatever part of its
            purpose remains meaningful.

      (For example, a function in a library to compute square roots has a
      purpose that is entirely well-defined independent of the
      application. Therefore, Subsection 2d requires that any
      application-supplied function or table used by this function must be
      optional: if the application does not supply it, the square root
      function must still compute square roots.)

      These requirements apply to the modified work as a whole. If
      identifiable sections of that work are not derived from the Library, and
      can be reasonably considered independent and separate works in
      themselves, then this License, and its terms, do not apply to those
      sections when you distribute them as separate works. But when you
      distribute the same sections as part of a whole which is a work based on
      the Library, the distribution of the whole must be on the terms of this
      License, whose permissions for other licensees extend to the entire
      whole, and thus to each and every part regardless of who wrote it.

      Thus, it is not the intent of this section to claim rights or contest
      your rights to work written entirely by you; rather, the intent is to
      exercise the right to control the distribution of derivative or
      collective works based on the Library.

      In addition, mere aggregation of another work not based on the Library
      with the Library (or with a work based on the Library) on a volume of a
      storage or distribution medium does not bring the other work under the
      scope of this License.


   3. You may opt to apply the terms of the ordinary GNU General Public
      License instead of this License to a given copy of the Library. To do
      this, you must alter all the notices that refer to this License, so that
      they refer to the ordinary GNU General Public License, version 2,
      instead of to this License. (If a newer version than version 2 of the
      ordinary GNU General Public License has appeared, then you can specify
      that version instead if you wish.) Do not make any other change in these
      notices.

      Once this change is made in a given copy, it is irreversible for that
      copy, so the ordinary GNU General Public License applies to all
      subsequent copies and derivative works made from that copy.

      This option is useful when you wish to copy part of the code of the
      Library into a program that is not a library.


   4. You may copy and distribute the Library (or a portion or derivative of
      it, under Section 2) in object code or executable form under the terms
      of Sections 1 and 2 above provided that you accompany it with the
      complete corresponding machine-readable source code, which must be
      distributed under the terms of Sections 1 and 2 above on a medium
      customarily used for software interchange.

      If distribution of object code is made by offering access to copy from a
      designated place, then offering equivalent access to copy the source code
      from the same place satisfies the requirement to distribute the source
      code, even though third parties are not compelled to copy the source along
      with the object code.


   5. A program that contains no derivative of any portion of the Library, but
      is designed to work with the Library by being compiled or linked with
      it, is called a "work that uses the Library". Such a work, in isolation,
      is not a derivative work of the Library, and therefore falls outside the
      scope of this License.

      However, linking a "work that uses the Library" with the Library creates
      an executable that is a derivative of the Library (because it contains
      portions of the Library), rather than a "work that uses the
      library". The executable is therefore covered by this License. Section 6
      states terms for distribution of such executables.

      When a "work that uses the Library" uses material from a header file
      that is part of the Library, the object code for the work may be a
      derivative work of the Library even though the source code is
      not. Whether this is true is especially significant if the work can be
      linked without the Library, or if the work is itself a library. The
      threshold for this to be true is not precisely defined by law.

      If such an object file uses only numerical parameters, data structure
      layouts and accessors, and small macros and small inline functions (ten
      lines or less in length), then the use of the object file is
      unrestricted, regardless of whether it is legally a derivative
      work. (Executables containing this object code plus portions of the
      Library will still fall under Section 6.)

      Otherwise, if the work is a derivative of the Library, you may
      distribute the object code for the work under the terms of Section 6. Any
      executables containing that work also fall under Section 6, whether or not
      they are linked directly with the Library itself.


   6. As an exception to the Sections above, you may also combine or link a
      "work that uses the Library" with the Library to produce a work
      containing portions of the Library, and distribute that work under terms
      of your choice, provided that the terms permit modification of the work
      for the customer's own use and reverse engineering for debugging such
      modifications.

      You must give prominent notice with each copy of the work that the
      Library is used in it and that the Library and its use are covered by
      this License. You must supply a copy of this License. If the work during
      execution displays copyright notices, you must include the copyright
      notice for the Library among them, as well as a reference directing the
      user to the copy of this License. Also, you must do one of these things:

         a. Accompany the work with the complete corresponding
            machine-readable source code for the Library including whatever
            changes were used in the work (which must be distributed under
            Sections 1 and 2 above); and, if the work is an executable linked
            with the Library, with the complete machine-readable "work that uses
            the Library", as object code and/or source code, so that the user
            can modify the Library and then relink to produce a modified
            executable containing the modified Library. (It is understood that
            the user who changes the contents of definitions files in the
            Library will not necessarily be able to recompile the application
            to use the modified definitions.) .

         b. Use a suitable shared library mechanism for linking with the
            Library. A suitable mechanism is one that (1) uses at run time a
            copy of the library already present on the user's computer system,
            rather than copying library functions into the executable, and (2)
            will operate properly with a modified version of the library, if
            the user installs one, as long as the modified version is
            interface-compatible with the version that the work was made with.

         c. Accompany the work with a written offer, valid for at least three
            years, to give the same user the materials specified in Subsection
            6a, above, for a charge no more than the cost of performing this
            distribution.

         d. If distribution of the work is made by offering access to copy
            from a designated place, offer equivalent access to copy the above
            specified materials from the same place. 

         e. Verify that the user has already received a copy of these
            materials or that you have already sent this user a copy.

      For an executable, the required form of the "work that uses the Library"
      must include any data and utility programs needed for reproducing the
      executable from it. However, as a special exception, the materials to be
      distributed need not include anything that is normally distributed (in
      either source or binary form) with the major components (compiler,
      kernel, and so on) of the operating system on which the executable runs,
      unless that component itself accompanies the executable.

      It may happen that this requirement contradicts the license restrictions
      of other proprietary libraries that do not normally accompany the
      operating system. Such a contradiction means you cannot use both them
      and the Library together in an executable that you distribute.


   7. You may place library facilities that are a work based on the Library
      side-by-side in a single library together with other library facilities
      not covered by this License, and distribute such a combined library,
      provided that the separate distribution of the work based on the Library
      and of the other library facilities is otherwise permitted, and provided
      that you do these two things:

         a. Accompany the combined library with a copy of the same work based
            on the Library, uncombined with any other library facilities. This
            must be distributed under the terms of the Sections above.

         b. Give prominent notice with the combined library of the fact that
            part of it is a work based on the Library, and explaining where to
            find the accompanying uncombined form of the same work. 


   8. You may not copy, modify, sublicense, link with, or distribute the
      Library except as expressly provided under this License. Any attempt
      otherwise to copy, modify, sublicense, link with, or distribute the
      Library is void, and will automatically terminate your rights under this
      License. However, parties who have received copies, or rights, from you
      under this License will not have their licenses terminated so long as
      such parties remain in full compliance.


   9. You are not required to accept this License, since you have not signed
      it. However, nothing else grants you permission to modify or distribute
      the Library or its derivative works. These actions are prohibited by law
      if you do not accept this License. Therefore, by modifying or
      distributing the Library (or any work based on the Library), you
      indicate your acceptance of this License to do so, and all its terms and
      conditions for copying, distributing or modifying the Library or works
      based on it.


  10. Each time you redistribute the Library (or any work based on the
      Library), the recipient automatically receives a license from the
      original licensor to copy, distribute, link with or modify the Library
      subject to these terms and conditions. You may not impose any further
      restrictions on the recipients' exercise of the rights granted
      herein. You are not responsible for enforcing compliance by third
      parties with this License. 


  11. If, as a consequence of a court judgment or allegation of patent
      infringement or for any other reason (not limited to patent issues),
      conditions are imposed on you (whether by court order, agreement or
      otherwise) that contradict the conditions of this License, they do not
      excuse you from the conditions of this License. If you cannot distribute
      so as to satisfy simultaneously your obligations under this License and
      any other pertinent obligations, then as a consequence you may not
      distribute the Library at all. For example, if a patent license would
      not permit royalty-free redistribution of the Library by all those who
      receive copies directly or indirectly through you, then the only way you
      could satisfy both it and this License would be to refrain entirely from
      distribution of the Library. 

      If any portion of this section is held invalid or unenforceable under
      any particular circumstance, the balance of the section is intended to
      apply, and the section as a whole is intended to apply in other
      circumstances.

      It is not the purpose of this section to induce you to infringe any
      patents or other property right claims or to contest validity of any
      such claims; this section has the sole purpose of protecting the
      integrity of the free software distribution system which is implemented
      by public license practices. Many people have made generous
      contributions to the wide range of software distributed through that
      system in reliance on consistent application of that system; it is up to
      the author/donor to decide if he or she is willing to distribute
      software through any other system and a licensee cannot impose that
      choice.

      This section is intended to make thoroughly clear what is believed to be
      a consequence of the rest of this License.


  12. If the distribution and/or use of the Library is restricted in certain
      countries either by patents or by copyrighted interfaces, the original
      copyright holder who places the Library under this License may add an
      explicit geographical distribution limitation excluding those countries,
      so that distribution is permitted only in or among countries not thus
      excluded. In such case, this License incorporates the limitation as if
      written in the body of this License.


  13. The Free Software Foundation may publish revised and/or new versions of
      the Lesser General Public License from time to time. Such new versions
      will be similar in spirit to the present version, but may differ in
      detail to address new problems or concerns.

      Each version is given a distinguishing version number. If the Library
      specifies a version number of this License which applies to it and "any
      later version", you have the option of following the terms and conditions
      either of that version or of any later version published by the Free
      Software Foundation. If the Library does not specify a license version
      number, you may choose any version ever published by the Free Software
      Foundation.


  14. If you wish to incorporate parts of the Library into other free programs
      whose distribution conditions are incompatible with these, write to the
      author to ask for permission. For software which is copyrighted by the
      Free Software Foundation, write to the Free Software Foundation; we
      sometimes make exceptions for this. Our decision will be guided by the
      two goals of preserving the free status of all derivatives of our free
      software and of promoting the sharing and reuse of software generally.

       No Warranty

  15. Because the library is licensed free of charge, there is no warranty for
      the library, to the extent permitted by applicable law. Except when
      otherwise stated in writing the copyright holders and/or other parties
      provide the library "as is" without warranty of any kind, either expressed
      or implied, including, but not limited to, the implied warranties of
      merchantability and fitness for a particular purpose. The entire risk as
      to the quality and performance of the library is with you. Should the
      library prove defective, you assume the cost of all necessary servicing,
      repair or correction.

  16. In no event unless required by applicable law or agreed to in writing
      will any copyright holder, or any other party who may modify and/or
      redistribute the library as permitted above, be liable to you for
      damages, including any general, special, incidental or consequential
      damages arising out of the use or inability to use the library
      (including but not limited to loss of data or data being rendered
      inaccurate or losses sustained by you or third parties or a failure of
      the library to operate with any other software), even if such holder or
      other party has been advised of the possibility of such damages.