path: root/libotr/libgpg-error-1.42/doc/gpgrt.info

This is gpgrt.info, produced by makeinfo version 6.5 from gpgrt.texi.

This manual is for Libgpg-error (version 1.42, 7 December 2018), which
is a library for code used by all GnuPG related packages.

Copyright (C) 2014 g10 Code GmbH

     Permission is granted to copy, distribute and/or modify this
     document under the terms of the GNU General Public License as
     published by the Free Software Foundation; either version 2 of the
     License, or (at your option) any later version.  The text of the
     license can be found in the section entitled "GNU General Public
     License".
INFO-DIR-SECTION Libraries
START-INFO-DIR-ENTRY
* libgpg-error: (gnupg).   Error codes and common code for GnuPG.
END-INFO-DIR-ENTRY


File: gpgrt.info,  Node: Top,  Next: Introduction,  Up: (dir)

The Libgpg-error Library
************************

This manual is for Libgpg-error (version 1.42, 7 December 2018), which
is a library for code used by all GnuPG related packages.

Copyright (C) 2014 g10 Code GmbH

     Permission is granted to copy, distribute and/or modify this
     document under the terms of the GNU General Public License as
     published by the Free Software Foundation; either version 2 of the
     License, or (at your option) any later version.  The text of the
     license can be found in the section entitled "GNU General Public
     License".

* Menu:

* Introduction::                 What is Libgpg-error.
* Preparation::                  What you should do before using the library.
* Generalities::                 General library functions and data types.
* Tools::                        Utility tools

Appendices

* Library Copying::             The GNU Lesser General Public License
                                says how you can copy and share Libgpg-error.
* Copying::                     The GNU General Public License says how you
                                can copy and share some parts of Libgpg-error.

Indices

* Concept Index::               Index of concepts and programs.
* Function and Data Index::     Index of functions, variables and data types.


File: gpgrt.info,  Node: Introduction,  Next: Preparation,  Prev: Top,  Up: Top

1 Introduction
**************

Libgpg-error is a library to provide error codes for GnuPG and relates
software as well as some other general purpose functions.  It is planned
to eventually rename this library to "gpgrt" (for GnuPG RunTime).

* Menu:

* Getting Started::             How to use this manual.
* Features::                    A glance at Libgpg-error’s features.
* Overview::                    Overview about the library.


File: gpgrt.info,  Node: Getting Started,  Next: Features,  Up: Introduction

1.1 Getting Started
===================

This manual documents the Libgpg-error library application programming
interface (API). The goal is to that all functions and data types
provided by the library are explained.  However, for now this is only a
stub and not very useful.


File: gpgrt.info,  Node: Features,  Next: Overview,  Prev: Getting Started,  Up: Introduction

1.2 Features
============

TBD


File: gpgrt.info,  Node: Overview,  Prev: Features,  Up: Introduction

1.3 Overview
============

The Libgpg-error library is fully thread-safe, where it makes sense to
be thread-safe.

   TBD


File: gpgrt.info,  Node: Preparation,  Next: Generalities,  Prev: Introduction,  Up: Top

2 Preparation
*************

To use Libgpg-error, you have to perform some changes to your sources
and the build system.  The necessary changes are small and explained in
the following sections.  At the end of this chapter, it is described how
the library is initialized, and how the requirements of the library are
verified.

* Menu:

* Header::                      What header file you need to include.
* Building sources::            How to build sources using the library.
* Building sources using Automake::  How to build sources with the help of Automake.
* Initializing the library::    How to initialize the library.
* Multi-Threading::             How Libgpg-error can be used in a MT environment.


File: gpgrt.info,  Node: Header,  Next: Building sources,  Up: Preparation

2.1 Header
==========

All interfaces (data types and functions) of the library are defined in
the header file 'libgpg-error.h'.  You must include this in all source
files using the library, either directly or through some other header
file, like this:

     #include <libgpg-error.h>

   Note well that the header file is platform specific and may only be
used on the platform for which it has been build.

   The name space of Libgpg-error is 'gpg_*' and 'gpgrt*' for function
and type names and 'GPG_*' and 'GPGRT_*' for other symbols.  In addition
the same name prefixes with one prepended underscore are reserved for
internal use and should never be used by an application.

Certain parts of gpg-error.h may be included by defining these macros:

'GPG_ERR_ENABLE_GETTEXT_MACROS'
     Define to provide macros to map the internal gettext API to
     standard names.  This has only an effect on Windows platforms.

'GPGRT_ENABLE_ES_MACROS'
     Define to provide "es_" macros for the estream functions.


File: gpgrt.info,  Node: Building sources,  Next: Building sources using Automake,  Prev: Header,  Up: Preparation

2.2 Building sources
====================

If you want to compile a source file including the 'gpg-error.h' header
file, you must make sure that the compiler can find it in the directory
hierarchy.  This is accomplished by adding the path to the directory in
which the header file is located to the compilers include file search
path (via the '-I' option).

   However, the path to the include file is determined at the time the
source is configured.  To solve this problem, Libgpg-error ships with
the small helper program 'gpgrt-config' which know the path to the
include file and other configuration options.  The options that need to
be added to the compiler invocation at compile time are output by the
'--cflags' option to 'gpgrt-config' The following example shows how it
can be used at the command line:

     gcc -c foo.c $(gpgrt-config --cflags)

   Adding the output of 'gpgrt-config --cflags' to the compiler’s
command line will ensure that the compiler can find the Libgpg-error
header file.

   A similar problem occurs when linking the program with the library.
Again, the compiler has to find the library files.  For this to work,
the path to the library files has to be added to the library search path
(via the '-L' option).  For this, the option '--libs' to 'gpgrt-config'
can be used.  The example shows how to link 'foo.o' with the
Libgpg-error library to a program 'foo'.

     gcc -o foo foo.o $(gpgrt-config --libs)

   Of course you can also combine both examples to a single command by
specifying both options to 'gpgrt-config':

     gcc -o foo foo.c $(gpgrt-config --cflags --libs)


File: gpgrt.info,  Node: Building sources using Automake,  Next: Initializing the library,  Prev: Building sources,  Up: Preparation

2.3 Building sources using Automake
===================================

It is much easier if you use GNU Automake instead of writing your own
Makefiles.  If you do that, you do not have to worry about finding and
invoking the 'gpgrt-config' script at all.  Libgpg-error provides an
extension to Automake that does all the work for you.

 -- Macro: AM_PATH_GPG_ERROR ([MINIMUM-VERSION], [ACTION-IF-FOUND],
          [ACTION-IF-NOT-FOUND])
     Check whether Libgpg-error (at least version MINIMUM-VERSION, if
     given) exists on the host system.  If it is found, execute
     ACTION-IF-FOUND, otherwise do ACTION-IF-NOT-FOUND, if given.

     Additionally, the function defines 'GPG_ERROR_CFLAGS' to the flags
     needed for compilation of the program to find the 'gpg-error.h'
     header file, and 'GPG_ERROR_LIBS' to the linker flags needed to
     link the program to the Libgpg-error library.  If the used helper
     script does not match the target type you are building for a
     warning is printed and the string 'libgpg-error' is appended to the
     variable 'gpg_config_script_warn'.

     This macro searches for 'gpgrt-config' along the PATH. If you are
     cross-compiling, it is useful to set the environment variable
     'SYSROOT' to the top directory of your target.  The macro will then
     first look for the helper program in the 'bin' directory below that
     top directory.  An absolute directory name must be used for
     'SYSROOT'.  Finally, if the configure command line option
     '--with-libgpg-error-prefix' is used, only its value is used for
     the top directory below which the helper script is expected.

   You can use the defined Autoconf variables like this in your
'Makefile.am':

     AM_CPPFLAGS = $(GPG_ERROR_CFLAGS)
     LDADD = $(GPG_ERROR_LIBS)


File: gpgrt.info,  Node: Initializing the library,  Next: Multi-Threading,  Prev: Building sources using Automake,  Up: Preparation

2.4 Initializing the library
============================

Before the library can be used, it should initialize itself.  This is
achieved by invoking the function 'gpgrt_check_version' described below.

   Also, it is often desirable to check that the version of Libgpg-error
used is indeed one which fits all requirements.  Even with binary
compatibility, new features may have been introduced, but due to problem
with the dynamic linker an old version may actually be used.  So you may
want to check that the version is okay right after program startup.

 -- Function: const char * gpgrt_check_version (const char *REQ_VERSION)

     The function 'gpgrt_check_version' initializes some subsystems used
     by Libgpg-error and must be invoked before any other function in
     the library.  *Note Multi-Threading::.

     Furthermore, this function returns the version number of the
     library.  It can also verify that the version number is higher than
     a certain required version number REQ_VERSION, if this value is not
     a null pointer.


File: gpgrt.info,  Node: Multi-Threading,  Prev: Initializing the library,  Up: Preparation

2.5 Multi-Threading
===================

TBD.


File: gpgrt.info,  Node: Generalities,  Next: Tools,  Prev: Preparation,  Up: Top

3 Generalities
**************

TBD. (Description of the error function may be taken from Libgcrypt.)


File: gpgrt.info,  Node: Tools,  Next: Library Copying,  Prev: Generalities,  Up: Top

4 Tools
*******

* Menu:

* gpgrt-config::    Print required compiler flags


File: gpgrt.info,  Node: gpgrt-config,  Up: Tools

4.1 Print required compiler flags
=================================

'gpgrt-config' is a tool that is used to configure to determine the
compiler and linker flags that should be used to compile and link
programs that use Libgpg-error.  It is also used internally to the '.m4'
macros for GNU autoconf that are included with Libgpg-error.

'gpgrt-config' accepts the following options:

'--mt'
     Provide output appropriate for multithreaded programs.  '--mt' is
     only useful when combined with other options, and must be the first
     option if present.

'--version'
     Print the currently installed version of Libgpg-error on the
     standard output.

'--libs'
     Print the linker flags that are necessary to link a program using
     Libgpg-error.

'--cflags'
     Print the compiler flags that are necessary to compile a program
     using Libgpg-error.

'--prefix=PREFIX'
     If specified, use PREFIX instead of the installation prefix that
     Libgpg-error was built with when computing the output for the
     '--cflags' and '--libs' options.  This option is also used for the
     exec prefix if '--exec-prefix' was not specified.  This option must
     be specified before any '--libs' or '--cflags' options.

'--exec-prefix=PREFIX'
     If specified, use PREFIX instead of the installation exec prefix
     that Libgpg-error was built with when computing the output for the
     '--cflags' and '--libs' options.  This option must be specified
     before any '--libs' or '--cflags' options.


File: gpgrt.info,  Node: Library Copying,  Next: Copying,  Prev: Tools,  Up: Top

GNU Lesser General Public License
*********************************

                      Version 2.1, February 1999

     Copyright (C) 1991, 1999 Free Software Foundation, Inc.
     59 Temple Place - Suite 330, Boston, MA 02111-1307, USA

     Everyone is permitted to copy and distribute verbatim copies
     of this license document, but changing it is not allowed.

     [This is the first released version of the Lesser GPL.  It also counts
     as the successor of the GNU Library Public License, version 2, hence the
     version number 2.1.]

Preamble
========

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     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.

                      END OF TERMS AND CONDITIONS

How to Apply These Terms to Your New Libraries
==============================================

If you develop a new library, and you want it to be of the greatest
possible use to the public, we recommend making it free software that
everyone can redistribute and change.  You can do so by permitting
redistribution under these terms (or, alternatively, under the terms of
the ordinary General Public License).

   To apply these terms, attach the following notices to the library.
It is safest to attach them to the start of each source file to most
effectively convey the exclusion of warranty; and each file should have
at least the "copyright" line and a pointer to where the full notice is
found.

     ONE LINE TO GIVE THE LIBRARY'S NAME AND AN IDEA OF WHAT IT DOES.
     Copyright (C) YEAR  NAME OF AUTHOR

     This library is free software; you can redistribute it and/or modify it
     under the terms of the GNU Lesser General Public License as published by
     the Free Software Foundation; either version 2.1 of the License, or (at
     your option) any later version.

     This library is distributed in the hope that it will be useful, but
     WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     Lesser General Public License for more details.

     You should have received a copy of the GNU Lesser General Public
     License along with this library; if not, write to the Free Software
     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307,
     USA.

   Also add information on how to contact you by electronic and paper
mail.

   You should also get your employer (if you work as a programmer) or
your school, if any, to sign a "copyright disclaimer" for the library,
if necessary.  Here is a sample; alter the names:

     Yoyodyne, Inc., hereby disclaims all copyright interest in the library
     `Frob' (a library for tweaking knobs) written by James Random Hacker.

     SIGNATURE OF TY COON, 1 April 1990
     Ty Coon, President of Vice

   That's all there is to it!


File: gpgrt.info,  Node: Copying,  Next: Concept Index,  Prev: Library Copying,  Up: Top

GNU General Public License
**************************

                         Version 2, June 1991

     Copyright (C) 1989, 1991 Free Software Foundation, Inc.
     59 Temple Place - Suite 330, Boston, MA 02111-1307, USA

     Everyone is permitted to copy and distribute verbatim copies
     of this license document, but changing it is not allowed.

Preamble
========

The licenses for most software are designed to take away your freedom to
share and change it.  By contrast, the GNU General Public License is
intended to guarantee your freedom to share and change free software--to
make sure the software is free for all its users.  This General Public
License applies to most of the Free Software Foundation's software and
to any other program whose authors commit to using it.  (Some other Free
Software Foundation software is covered by the GNU Library General
Public License instead.)  You can apply it to your programs, too.

   When we speak of free software, we are referring to freedom, not
price.  Our General Public Licenses are designed to make sure that you
have the freedom to distribute copies of free software (and charge for
this service if you wish), that you receive source code or can get it if
you want it, that you can change the software or use pieces of it in new
free programs; and that you know you can do these things.

   To protect your rights, we need to make restrictions that forbid
anyone to deny you these rights or to ask you to surrender the rights.
These restrictions translate to certain responsibilities for you if you
distribute copies of the software, or if you modify it.

   For example, if you distribute copies of such a program, whether
gratis or for a fee, you must give the recipients all the rights that
you have.  You must make sure that they, too, receive or can get the
source code.  And you must show them these terms so they know their
rights.

   We protect your rights with two steps: (1) copyright the software,
and (2) offer you this license which gives you legal permission to copy,
distribute and/or modify the software.

   Also, for each author's protection and ours, we want to make certain
that everyone understands that there is no warranty for this free
software.  If the software is modified by someone else and passed on, we
want its recipients to know that what they have is not the original, so
that any problems introduced by others will not reflect on the original
authors' reputations.

   Finally, any free program is threatened constantly by software
patents.  We wish to avoid the danger that redistributors of a free
program will individually obtain patent licenses, in effect making the
program proprietary.  To prevent this, we have made it clear that any
patent must be licensed for everyone's free use or not licensed at all.

   The precise terms and conditions for copying, distribution and
modification follow.

    TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION

  1. This License applies to any program or other work which contains a
     notice placed by the copyright holder saying it may be distributed
     under the terms of this General Public License.  The "Program",
     below, refers to any such program or work, and a "work based on the
     Program" means either the Program or any derivative work under
     copyright law: that is to say, a work containing the Program or a
     portion of it, either verbatim or with modifications and/or
     translated into another language.  (Hereinafter, translation is
     included without limitation in the term "modification".)  Each
     licensee is addressed as "you".

     Activities other than copying, distribution and modification are
     not covered by this License; they are outside its scope.  The act
     of running the Program is not restricted, and the output from the
     Program is covered only if its contents constitute a work based on
     the Program (independent of having been made by running the
     Program).  Whether that is true depends on what the Program does.

  2. You may copy and distribute verbatim copies of the Program's 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 give any other recipients of the Program a copy of
     this License along with the Program.

     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.

  3. You may modify your copy or copies of the Program or any portion of
     it, thus forming a work based on the Program, 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. You must cause the modified files to carry prominent notices
          stating that you changed the files and the date of any change.

       b. You must cause any work that you distribute or publish, that
          in whole or in part contains or is derived from the Program or
          any part thereof, to be licensed as a whole at no charge to
          all third parties under the terms of this License.

       c. If the modified program normally reads commands interactively
          when run, you must cause it, when started running for such
          interactive use in the most ordinary way, to print or display
          an announcement including an appropriate copyright notice and
          a notice that there is no warranty (or else, saying that you
          provide a warranty) and that users may redistribute the
          program under these conditions, and telling the user how to
          view a copy of this License.  (Exception: if the Program
          itself is interactive but does not normally print such an
          announcement, your work based on the Program is not required
          to print an announcement.)

     These requirements apply to the modified work as a whole.  If
     identifiable sections of that work are not derived from the
     Program, 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 Program, 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 Program.

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

  4. You may copy and distribute the Program (or a work based on it,
     under Section 2) in object code or executable form under the terms
     of Sections 1 and 2 above provided that you also do one of the
     following:

       a. 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; or,

       b. Accompany it with a written offer, valid for at least three
          years, to give any third party, for a charge no more than your
          cost of physically performing source distribution, a complete
          machine-readable copy of the corresponding source code, to be
          distributed under the terms of Sections 1 and 2 above on a
          medium customarily used for software interchange; or,

       c. Accompany it with the information you received as to the offer
          to distribute corresponding source code.  (This alternative is
          allowed only for noncommercial distribution and only if you
          received the program in object code or executable form with
          such an offer, in accord with Subsection b above.)

     The source code for a work means the preferred form of the work for
     making modifications to it.  For an executable work, 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 executable.
     However, as a special exception, the source code 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.

     If distribution of executable or 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 counts as
     distribution of the source code, even though third parties are not
     compelled to copy the source along with the object code.

  5. You may not copy, modify, sublicense, or distribute the Program
     except as expressly provided under this License.  Any attempt
     otherwise to copy, modify, sublicense or distribute the Program 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.

  6. 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 Program or its derivative works.  These actions
     are prohibited by law if you do not accept this License.
     Therefore, by modifying or distributing the Program (or any work
     based on the Program), you indicate your acceptance of this License
     to do so, and all its terms and conditions for copying,
     distributing or modifying the Program or works based on it.

  7. Each time you redistribute the Program (or any work based on the
     Program), the recipient automatically receives a license from the
     original licensor to copy, distribute or modify the Program 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 to this License.

  8. 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
     Program at all.  For example, if a patent license would not permit
     royalty-free redistribution of the Program 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 Program.

     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.

  9. If the distribution and/or use of the Program is restricted in
     certain countries either by patents or by copyrighted interfaces,
     the original copyright holder who places the Program 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.

  10. The Free Software Foundation may publish revised and/or new
     versions of the 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
     Program 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 Program does not
     specify a version number of this License, you may choose any
     version ever published by the Free Software Foundation.

  11. If you wish to incorporate parts of the Program into other free
     programs whose distribution conditions are different, 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

  12. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO
     WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE
     LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS
     AND/OR OTHER PARTIES PROVIDE THE PROGRAM "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 PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE
     DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR
     OR CORRECTION.

  13. 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 PROGRAM 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 PROGRAM (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 PROGRAM TO OPERATE WITH ANY
     OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN
     ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

                      END OF TERMS AND CONDITIONS

How to Apply These Terms to Your New Programs
=============================================

If you develop a new program, and you want it to be of the greatest
possible use to the public, the best way to achieve this is to make it
free software which everyone can redistribute and change under these
terms.

   To do so, attach the following notices to the program.  It is safest
to attach them to the start of each source file to most effectively
convey the exclusion of warranty; and each file should have at least the
"copyright" line and a pointer to where the full notice is found.

     ONE LINE TO GIVE THE PROGRAM'S NAME AND AN IDEA OF WHAT IT DOES.
     Copyright (C) 19YY  NAME OF AUTHOR

     This program is free software; you can redistribute it and/or
     modify it under the terms of the GNU General Public License
     as published by the Free Software Foundation; either version 2
     of the License, or (at your option) any later version.

     This program is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU General Public License for more details.

     You should have received a copy of the GNU General Public License along
     with this program; if not, write to the Free Software Foundation, Inc.,
     59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.

   Also add information on how to contact you by electronic and paper
mail.

   If the program is interactive, make it output a short notice like
this when it starts in an interactive mode:

     Gnomovision version 69, Copyright (C) 19YY NAME OF AUTHOR
     Gnomovision comes with ABSOLUTELY NO WARRANTY; for details
     type `show w'.  This is free software, and you are welcome
     to redistribute it under certain conditions; type `show c'
     for details.

   The hypothetical commands 'show w' and 'show c' should show the
appropriate parts of the General Public License.  Of course, the
commands you use may be called something other than 'show w' and 'show
c'; they could even be mouse-clicks or menu items--whatever suits your
program.

   You should also get your employer (if you work as a programmer) or
your school, if any, to sign a "copyright disclaimer" for the program,
if necessary.  Here is a sample; alter the names:

     Yoyodyne, Inc., hereby disclaims all copyright
     interest in the program `Gnomovision'
     (which makes passes at compilers) written
     by James Hacker.

     SIGNATURE OF TY COON, 1 April 1989
     Ty Coon, President of Vice

   This General Public License does not permit incorporating your
program into proprietary programs.  If your program is a subroutine
library, you may consider it more useful to permit linking proprietary
applications with the library.  If this is what you want to do, use the
GNU Library General Public License instead of this License.


File: gpgrt.info,  Node: Concept Index,  Next: Function and Data Index,  Prev: Copying,  Up: Top

Concept Index
*************

[index]
* Menu:

* GPL, GNU General Public License:       Copying.               (line 6)
* LGPL, GNU Lesser General Public License: Library Copying.     (line 6)


File: gpgrt.info,  Node: Function and Data Index,  Prev: Concept Index,  Up: Top

Function and Data Index
***********************

[index]
* Menu:

* AM_PATH_GPG_ERROR:                     Building sources using Automake.
                                                               (line 11)
* gpgrt_check_version:                   Initializing the library.
                                                               (line 15)



Tag Table:
Node: Top729
Node: Introduction2103
Node: Getting Started2625
Node: Features2982
Node: Overview3111
Node: Preparation3307
Node: Header4108
Node: Building sources5193
Node: Building sources using Automake6924
Node: Initializing the library8861
Node: Multi-Threading10049
Node: Generalities10191
Node: Tools10378
Node: gpgrt-config10544
Node: Library Copying12111
Node: Copying40212
Node: Concept Index59382
Node: Function and Data Index59679

End Tag Table