模块和扩展快速入门
SUSE Linux Enterprise Desktop 15 SP5

# 模块和扩展快速入门 #

出版日期： 2025 年 12 月 11 日

本快速入门提供了 SUSE Linux Enterprise 系列可用模块和扩展的概述。您可以了解它们的用途和功能，以及如何管理它们。

修订历史: 模块和扩展快速入门

## 1 模块和扩展简介 #

从 SUSE Linux Enterprise Desktop 15 开始，安装媒体仅包含统一安装程序：一个用于部署、更新和注册 SUSE Linux Enterprise Desktop 的精简系统。在部署期间，您可以通过选择要在统一安装程序的基础上安装的模块和扩展来添加功能。

从技术上讲，模块和扩展非常类似。可以使用 YaST 或命令行工具 `SUSEConnect` 管理两者。模块和扩展都会添加一组包含所有必要软件包的联机储存库（`main`、`update`、`source`、`debug`）。此外，它们都可添加可以在部署期间选择的分区建议和系统角色。

不过，模块和扩展之间也存在一些重大差异：

模块

  模块可让您根据需要定制产品功能。每个模块都有明确定义的范围，从用于进行 Web 开发和编写脚本的工具到公共云、再到 SUSE Package Hub（提供由社区管理的软件包）。

  利用模块，您可以仅提供满足计算机用途所需的一组软件包，从而精简系统、加快其运行速度，并提高其安全性。这种模块化方法还可让您轻松提供专为容器和云环境定制的映像。

  您可以在系统的整个生命周期内随时添加或去除模块。这样您便可轻松调整系统以满足不断变化的要求。

  模块属于您的 SUSE Linux Enterprise Desktop 订阅的一部分，因此可免费使用。模块与 SUSE Linux Enterprise Desktop 基础系统的唯一不同之处就是生命周期。SUSE 为模块所提供的几乎所有软件包都提供 L3 支持（SUSE Package Hub 模块除外）。有关 SUSE Linux Enterprise Desktop 支持声明的详细信息，请参见相应发行说明。

扩展

  扩展为 SUSE Linux Enterprise Desktop 的实时修补和高可用性群集组建等任务提供高级功能。它们以订阅的形式提供，需要注册密钥，因此需付费才能使用。https://www.suse.com/releasenotes 上通常会提供各扩展的发行说明。

### 1.1 支持 #

一般会对软件包提供 L3 支持（`SUSE Package Hub` 和第三方模块除外）。要检查软件包的支持级别，请运行 `zypper info PACKAGE`。

`Long-Term Service Pack Support` (LTSS) 适用于大多数模块和扩展。有关详细信息，请参见 Long-Term Service Pack Support。

某些模块和扩展还附带 `Extended Service Pack Overlay Support` (ESPOS)。有关详细信息，请参见 Extended Service Pack Overlay Support。

有关支持和生命周期的详细信息，请参见 SUSE Technical Support Policy 和 Product Lifecycle Support Policies。如需各产品生命周期日期的完整列表，请参见 Product Support Lifecycle 页面。

## 2 SUSE Linux Enterprise 产品系列的模块和扩展 #

SUSE Linux Enterprise 产品系列中提供下列模块和扩展：

- Basesystem

- Certifications

- Desktop Applications

- Development Tools

- Python 3

- SUSE Package Hub

- Workstation Extension

请注意，可用性视产品而定。并非所有模块和扩展都可用于所有产品。有些模块包含在一个产品中，但也可以用作另一个产品的扩展。

### 2.1 Basesystem #

此模块在安装程序的基础上添加一个基本系统。其他所有模块和扩展都需要此模块。只包含基础系统的安装范围相当于旧版 SUSE Linux Enterprise Desktop 的 `minimal` 系统安装软件集。系统默认已选择安装此软件集，不应将其取消选择。

- 依赖项：无

- 可用性：默认所有产品上均提供

- 生命周期：10 年

- 扩展支持：3 年 LTSS

- 支持级别：L3

### 2.2 Certifications #

此模块包含 FIPS 认证软件包。

- 依赖项：Basesystem

- 适用于：SLES、SLED、SLES-SAP、SUSE Linux Enterprise Real Time、SLE-HPC

- 生命周期：10 年

- 扩展支持：3 年 LTSS

- 支持级别：L3

### 2.3 Desktop Applications #

此模块可向系统添加图形用户界面 (Wayland) 和最基本的桌面应用程序。系统默认已选择安装此模块；不建议将其取消选择。

- 依赖项：Basesystem

- 可用性：SLES、SLED（默认）、SLE-WE（默认）、SLES-SAP、SLE-RT（默认）、SLE-HPC

- 生命周期：10 年

- 扩展支持：3 年 LTSS

- 级别：L3

### 2.4 Development Tools #

此模块包含编译及调试应用程序所需的编译器（包括 gcc）和库。取代了以前的 Software Development Kit (SDK)。

依赖项：Basesystem、Desktop Applications

- 可用性：SLES、SLES-SAP、SLED、SLE-RT（默认）、SLE-HPC

- 生命周期：10 年

- 扩展支持：3 年 LTSS

- 级别：L3

### 2.5 Python 3 #

此模块包含选定 Python 3 软件包的最新版本。它的生命周期与 SUSE Linux Enterprise 产品本身不同。此模块中的软件包会频繁地更新到新的上游版本。

- 依赖项：Basesystem

- 可用性：SLES、SLES-SAP、SLE-HPC、SLED

- 生命周期：10 年

- 扩展支持：无

- 级别：L3

### 2.6 SUSE Package Hub #

此模块用于访问 openSUSE 社区维护的各个 SUSE Linux Enterprise Desktop 软件包。对于这些软件包不提供 L3 支持，但这不影响对 SUSE Linux Enterprise Desktop 的支持。有关详细信息，请参见 https://packagehub.suse.com/。

- 依赖项：Basesystem

- 适用于：SLES、SLES-SAP、SLED、SLE-HPC

- 生命周期：无

- 扩展支持：无

- 级别：无

### 2.7 Workstation Extension #

此扩展提供额外的桌面应用程序和库。SUSE Linux Enterprise Desktop 上默认已安装该扩展。通过在 SUSE Linux Enterprise Server 安装中添加 Workstation Extension，您可以将这两个产品无缝融合，以创建功能完备的服务器工作站。有关详细信息，请参见 https://www.suse.com/products/workstation-extension。

警告：不支持的内核模块

Workstation Extension 安装 kernel-default-extra 软件包，该软件包包含用于桌面用途的其他内核模块，并可用于装载不受支持的模块。如果实际装载这些模块，它们可能会影响您的 SLE 支持状态。

请评估您的硬件是否确实需要其他内核模块，如果需要，请测试此扩展驱动程序集以及 kernel-default 软件包中的默认驱动程序集是否可能存在配置冲突。

要阻止安装 kernel-default-extra 软件包，请运行 `zypper addlock kernel-default-extra`。

- 依赖项：Basesystem、Desktop

- 可用性：SLES、SLED（默认）、SLES-SAP

- 生命周期：10 年

- 扩展支持：无

- 级别：混合的 L2/L3（取决于软件包）

## 3 安装和管理模块与扩展 #

在最初设置系统时以及在现有的 SUSE Linux Enterprise Desktop 安装上可以安装模块和扩展。

### 3.1 在系统安装期间安装模块和扩展 #

在设置系统时可以轻松安装模块和扩展。相应步骤属于安装例程的一部分。如果使用默认安装路径，您需要拥有网络访问权限以访问提供相应储存库的 SUSE Customer Center 或本地注册服务器（SUSE Manager 或 Repository Mirroring Tool）。您也可以采用脱机安装方式。脱机安装需要额外的安装媒体。有关详细信息，请参见Book “Deployment Guide”, Chapter 4 “Installation steps”, Section 4.7 “Extension and module selection”。

### 3.2 使用 YaST 安装模块和扩展 #

要从正在运行的系统安装模块和扩展，您需要确保系统已在 SUSE Customer Center 或本地注册服务器中注册。如果您在安装期间未注册系统，请参考Book “Deployment Guide”, Chapter 5 “Registering SUSE Linux Enterprise and managing modules/extensions”, Section 5.2 “Registering from the installed system”中的相关说明。

提示：SUSE Linux Enterprise Desktop

从 SUSE Linux Enterprise 12 开始，SUSE Linux Enterprise Desktop 不仅作为独立的产品提供，还可作为 SUSE Linux Enterprise Server 的 Workstation 扩展提供。如果您在 SUSE Customer Center 上注册了产品，便可以选择安装 Workstation Extension。请注意，您需要提供有效的注册代码才能安装它。

注意：查看已安装的附加产品

要查看已安装的附加产品，请启动 YaST 并选择软件 › 附加产品

过程 1︰ 使用 YaST 从联机通道安装附加产品和扩展 #

1. 启动 YaST，然后选择软件 › 系统扩展。YaST 将连接到注册服务器并显示可用的扩展和模块列表。

   注意：可用扩展和模块

   可用扩展和模块数视注册服务器而定。本地注册服务器可能只提供更新储存库，而不提供其他扩展。

2. 单击一项可查看其说明。

3. 要添加模块或扩展，请选择您要安装的所有组件。请注意，需要为所有扩展提供付费购买的附加注册码。

4. 单击下一步继续。

5. 根据您为扩展或模块添加的储存库，系统可能会提示您导入储存库的 GPG 密钥，或者要求您同意许可条款。

6. YaST 软件包管理器将会打开，以安装每个模块的 `release` 软件包；根据您所选的模块和扩展，它还会安装其他的软件包。强烈建议不要取消选择系统预先选择的任何软件包；不过，您可以添加其他的软件包。

   依次选择接受和完成以完成该过程。

7. 如果需要，请根据Book “管理指南”, Chapter 8 “安装或去除软件”, Section 8.4.2 “管理储存库属性”中所述调整储存库的属性。

提示：模块依赖项

软件包可能需要依赖其他软件包才能正常运行，而模块与此类似，它们也可能依赖于其他模块。如果存在这种情况，系统会自动选择安装所依赖的模块。

### 3.3 从媒体安装扩展和第三方附加产品 #

从媒体安装扩展或附加产品时，您可以选择各种产品媒体，例如 DVD/CD、可移动大容量存储设备（如闪存盘）、本地目录或 ISO 映像。网络服务器也可以提供媒体，例如，通过 HTTP、FTP、NFS 或 Samba。

1. 启动 YaST，然后选择软件 › 附加产品。或者在命令行中使用 `sudo yast2 add-on` 启动 YaST 附加产品模块。

   对话框将显示已安装附加产品、模块和扩展的概览。

2. 单击添加以安装新的附加产品。

3. 在附加产品对话框中，选择与您要从中进行安装的媒体类型匹配的选项：

   - 要通过 SLP 在网络中扫描宣告了其服务的安装服务器，请选择使用 SLP 扫描，然后单击下一步。

   - 要从可卸媒体添加安装源，请选择相关选项，并在计算机中插入媒体或连接 USB 设备。单击下一步开始安装。

   - 对于大多数媒体类型，在选择相应的选项并单击下一步后，系统会提示您指定媒体的路径（或 URL）。可以选择性地指定储存库名称。如果不指定任何储存库名称，YaST 将使用产品的名称或 URL 作为储存库名称。

   默认情况下已激活下载储存库说明文件选项。如果停用该选项，YaST 稍后会根据需要自动下载这些文件。

4. 根据您添加的储存库，系统可能会提示您导入储存库的 GPG 密钥，或者要求您同意许可条款。

   确认这些消息后，YaST 将下载并分析元数据。它会将储存库添加到已配置储存库列表。

5. 如果需要，请根据Book “管理指南”, Chapter 8 “安装或去除软件”, Section 8.4.2 “管理储存库属性”中所述调整储存库的属性。

6. 单击确定确认所做的更改，并关闭配置对话框。

7. 成功添加附加产品媒体中的安装源后，软件管理器会启动，让您开始安装软件包。有关细节，请参见Book “管理指南”, Chapter 8 “安装或去除软件”。

### 3.4 使用 YaST 删除模块和扩展 #

1. 启动 YaST › 软件 › 附加产品。

2. 选择要去除的模块或扩展，然后单击删除。当有警告指出将要去除选定组件中的所有软件包时，请确认删除。

3. YaST 软件管理器此时将会打开，并列出已删除的模块或扩展中所有已安装的软件包。单击接受以去除所有这些软件包。强烈建议您去除不想要的软件包，因为对于已删除的模块或扩展中的软件包，系统不再提供其更新。如果您保留软件包，请务必至少去除每个已删除的模块或扩展的 `*-release` 软件包。

   依次单击接受和确定以继续。

警告：删除模块

请注意，切勿删除 Basesystem 模块。此外建议不要删除 SUSE Linux Enterprise Workstation Extension 和 Desktop Applications 模块。

警告：系统不会为已删除的模块和扩展中的软件包提供更新

如果您选择保留已删除模块或扩展中的软件包，将不再会收到这些软件包的更新。因为这些更新包括安全修复，保留此类软件包可能会给系统带来安全风险。

### 3.5 使用 SUSEConnect 添加或删除模块和扩展 #

1. 运行 `SUSEConnect --list-extensions` 获取可用扩展的概览：

       > sudo SUSEConnect -list-extensions
       AVAILABLE EXTENSIONS AND MODULES

           Basesystem Module 15 SP5 x86_64 (Activated)
           Deactivate with: SUSEConnect -d -p sle-module-basesystem/15.5/x86_64

               Desktop Applications Module 15 SP5 x86_64 (Activated)
               Deactivate with: SUSEConnect -d -p sle-module-desktop-applications/15.5/x86_64

                   Development Tools Module 15 SP5 x86_64
                   Activate with: SUSEConnect    -p sle-module-development-tools/15.5/x86_64

                   SUSE Linux Enterprise Workstation Extension 15 SP5 x86_64 (Activated)
                   Deactivate with: SUSEConnect -d -p sle-we/15.5/x86_64

               Python 3 Module 15 SP5 x86_64
               Activate with: SUSEConnect -p sle-module-python3/15.5/x86_64

               SUSE Package Hub 15 SP5 x86_64
               Activate with: SUSEConnect    -p PackageHub/15.5/x86_64

           Certifications Module 15 SP5 x86_64
           Activate with: SUSEConnect -p sle-module-certifications/15.5/x86_64

       REMARKS

       (Not available) The module/extension is not enabled on your RMT/SMT
       (Activated)     The module/extension is activated on your system

       MORE INFORMATION

       You can find more information about available modules here:
       https://www.suse.com/documentation/sles-15/singlehtml/art_modules/art_modules.html

2. 运行用于激活/停用模块或扩展的命令列表中的命令，以添加或删除组件。请注意，添加扩展需要提供付费购买的附加注册码。

警告：删除模块

请注意，切勿删除 Basesystem 模块。此外建议不要删除 SUSE Linux Enterprise Workstation Extension 和 Desktop Applications 模块。

重要：不会自动安装或去除软件包

`SUSEConnect` 只会添加或去除模块和扩展。它会注册或取消注册组件，并启用或禁用组件的储存库，但不会安装或去除任何软件包。如果您想要自动完成此类操作，请使用 YaST 来管理模块和扩展。

添加模块或扩展时，`SUSEConnect` 不会安装默认软件包或软件集。要手动执行此类操作，请使用 Zypper 或 YaST › 软件管理。

删除模块或扩展时，`SUSEConnect` 不会执行清理。模块或扩展中的软件包仍会安装在系统上，但不再从储存库更新。要列出这些“孤立的”软件包，请运行 `zypper packages --orphaned`。要去除一个或多个软件包，请运行 `zypper remove PACKAGE [ANOTHER_PACKAGE]`。或者，可以使用 YaST › 软件管理，然后使用视图 › 软件包分类 › 孤立的软件包列出和删除孤立的软件包。

警告：系统不会为已删除的模块和扩展中的软件包提供更新

如果您选择保留已删除模块或扩展中的软件包，将不再会收到这些软件包的更新。因为这些更新包括安全修复，保留此类软件包可能会给系统带来安全风险。

## 4 软件包的模块成员资格 #

默认情况下，用于搜索软件包的工具（YaST 软件管理或 `zypper search`）被限制为仅可在已激活的储存库中搜索。要将搜索范围扩展到尚未激活的远程储存库，您可以运行以下命令：

    zypper search-packages PACKAGE

提示：在 SUSE Customer Center 中搜索软件包

您还可以在 SUSE Customer Center Web 界面（网址为 https://scc.suse.com/packages）中搜索软件包及其相应模块。此服务不需要登录 SUSE。

`zypper search-packages` 提供了以下选项供您细化搜索结果：

`-x`，`--match-exact`

  搜索完全匹配项。

`-g`，`--group-by-module`

  按模块而非软件包名称对搜索结果分组。

`-d`，`--details`

  同时列出版本号和包含该软件包的储存库。

`--xmlout`

  生成 XML 输出。

下面是如何使用 `zypper search-packages` 的一些示例。

例 1︰ 简单搜索 #

下面的命令会搜索软件包 nodejs 和 hawk。第一个软件包在 `Web and Scripting` 模块中提供，第二个软件包属于 SUSE Linux Enterprise High Availability Extension 的一部分。这两个软件包都尚未安装：

    > zypper search-packages openjdk nodejs
    Following packages were found in following modules:

    Package          Module or Repository
                        SUSEConnect Activation Command
    --------------- ----------------------------------------------------------------
    ------------------ -------------------------------------------------------------
    java-11-openjdk  Basesystem Module (sle-module-basesystem/15.4/x86_64)
                        SUSEConnect --product sle-module-basesystem/15.4/x86_64
    java-17-openjdk  Basesystem Module (sle-module-basesystem/15.4/x86_64)
                        SUSEConnect --product sle-module-basesystem/15.4/x86_64
    nodejs14         Web and Scripting Module (sle-module-web-scripting/15.4/x86_64)
                        SUSEConnect --product sle-module-web-scripting/15.4/x86_64
    nodejs16         Web and Scripting Module (sle-module-web-scripting/15.4/x86_64)
                        SUSEConnect --product sle-module-web-scripting/15.4/x86_64
    [...]

例 2︰ 搜索完全匹配项 #

如果您知道确切的软件包名称，则可以使用选项 `-x` 将搜索结果缩小到完全匹配的软件包：

    > zypper search-packages -x java-11-openjdk nodejs14
    Following packages were found in following modules:

    Package          Module or Repository
                       SUSEConnect Activation Command
    --------------- ----------------------------------------------------------------
    ------------------ -------------------------------------------------------------
    java-11-openjdk  Basesystem Module (sle-module-basesystem/15.4/x86_64)
                       SUSEConnect --product sle-module-basesystem/15.4/x86_64
    nodejs14         Web and Scripting Module (sle-module-web-scripting/15.4/x86_64)
                       SUSEConnect --product sle-module-web-scripting/15.4/x86_64
    [...]

例 3︰ 搜索已安装或提供的软件包 #

如果您要搜索的软件包已安装或在您系统上可用的某个模块中提供，搜索结果会有所不同。下面的示例中已安装软件包 vim，未安装软件包 emacs，但您无需添加模块就可安装它。

    > zypper search-packages -x vim
    Following packages were found in following modules:

    Package  Module or Repository
               SUSEConnect Activation Command
    --- -------------------------------------------------------------------------------------
    ---------- ------------------------------------------------------------------------------
    vim Basesystem Module (sle-module-basesystem/15.4/x86_64)
          SUSEConnect --product sle-module-basesystem/15.4/x86_64
    vim Installed
    vim Available in repo Basesystem_Module_15_SP4_x86_64:SLE-Module-Basesystem15-SP4-Pool
    vim Available in repo Basesystem_Module_15_SP4_x86_64:SLE-Module-Basesystem15-SP4-Updates

    > zypper search-packages -x emacs
    Following packages were found in following modules:

    Package Module or Repository
              SUSEConnect Activation Command
    ----- ----------------------------------------------------------------------------------
    --------- ------------------------------------------------------------------------------
    emacs Basesystem Module (sle-module-basesystem/15.4/x86_64)
            SUSEConnect --product sle-module-basesystem/15.4/x86_64
    emacs Available in repo Basesystem_Module_15_SP4_x86_64:SLE-Module-Basesystem15-SP4-Pool

如果不搜索软件包，您还可以查看属于某个模块或扩展的软件包列表。启动 YaST 软件管理模块，然后单击查看 › 服务。选择一项以显示属于此模块或扩展的软件包列表。

## 5 法律声明 #

版权所有 © 2006–2025 SUSE LLC 和贡献者。保留所有权利。

根据 GNU 自由文档许可 (GNU Free Documentation License) 版本 1.2 或（根据您的选择）版本 1.3 中的条款，在此授予您复制、分发和/或修改本文档的权限；本版权声明和许可附带不可变部分。许可版本 1.2 的副本包含在题为“GNU Free Documentation License”的部分。

有关 SUSE 商标，请参见 https://www.suse.com/company/legal/。所有其他第三方商标分别为相应所有者的财产。商标符号（®、™ 等）代表 SUSE 及其关联公司的商标。星号 (*) 代表第三方商标。

本指南力求涵盖所有细节，但这不能确保本指南准确无误。SUSE LLC 及其关联公司、作者和译者对于可能出现的错误或由此造成的后果皆不承担责任。

## 6 GNU Free Documentation License #

Copyright (C) 2000, 2001, 2002 Free Software Foundation, Inc. 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.

##### 0. PREAMBLE #

The purpose of this License is to make a manual, textbook, or other functional and useful document "free" in the sense of freedom: to assure everyone the effective freedom to copy and redistribute it, with or without modifying it, either commercially or non-commercially. Secondarily, this License preserves for the author and publisher a way to get credit for their work, while not being considered responsible for modifications made by others.

This License is a kind of "copyleft", which means that derivative works of the document must themselves be free in the same sense. It complements the GNU General Public License, which is a copyleft license designed for free software.

We have designed this License to use it for manuals for free software, because free software needs free documentation: a free program should come with manuals providing the same freedoms that the software does. But this License is not limited to software manuals; it can be used for any textual work, regardless of subject matter or whether it is published as a printed book. We recommend this License principally for works whose purpose is instruction or reference.

##### 1. APPLICABILITY AND DEFINITIONS #

This License applies to any manual or other work, in any medium, that contains a notice placed by the copyright holder saying it can be distributed under the terms of this License. Such a notice grants a world-wide, royalty-free license, unlimited in duration, to use that work under the conditions stated herein. The "Document", below, refers to any such manual or work. Any member of the public is a licensee, and is addressed as "you". You accept the license if you copy, modify or distribute the work in a way requiring permission under copyright law.

A "Modified Version" of the Document means any work containing the Document or a portion of it, either copied verbatim, or with modifications and/or translated into another language.

A "Secondary Section" is a named appendix or a front-matter section of the Document that deals exclusively with the relationship of the publishers or authors of the Document to the Document's overall subject (or to related matters) and contains nothing that could fall directly within that overall subject. (Thus, if the Document is in part a textbook of mathematics, a Secondary Section may not explain any mathematics.) The relationship could be a matter of historical connection with the subject or with related matters, or of legal, commercial, philosophical, ethical or political position regarding them.

The "Invariant Sections" are certain Secondary Sections whose titles are designated, as being those of Invariant Sections, in the notice that says that the Document is released under this License. If a section does not fit the above definition of Secondary then it is not allowed to be designated as Invariant. The Document may contain zero Invariant Sections. If the Document does not identify any Invariant Sections then there are none.

The "Cover Texts" are certain short passages of text that are listed, as Front-Cover Texts or Back-Cover Texts, in the notice that says that the Document is released under this License. A Front-Cover Text may be at most 5 words, and a Back-Cover Text may be at most 25 words.

A "Transparent" copy of the Document means a machine-readable copy, represented in a format whose specification is available to the general public, that is suitable for revising the document straightforwardly with generic text editors or (for images composed of pixels) generic paint programs or (for drawings) some widely available drawing editor, and that is suitable for input to text formatters or for automatic translation to a variety of formats suitable for input to text formatters. A copy made in an otherwise Transparent file format whose markup, or absence of markup, has been arranged to thwart or discourage subsequent modification by readers is not Transparent. An image format is not Transparent if used for any substantial amount of text. A copy that is not "Transparent" is called "Opaque".

Examples of suitable formats for Transparent copies include plain ASCII without markup, Texinfo input format, LaTeX input format, SGML or XML using a publicly available DTD, and standard-conforming simple HTML, PostScript or PDF designed for human modification. Examples of transparent image formats include PNG, XCF and JPG. Opaque formats include proprietary formats that can be read and edited only by proprietary word processors, SGML or XML for which the DTD and/or processing tools are not generally available, and the machine-generated HTML, PostScript or PDF produced by some word processors for output purposes only.

The "Title Page" means, for a printed book, the title page itself, plus such following pages as are needed to hold, legibly, the material this License requires to appear in the title page. For works in formats which do not have any title page as such, "Title Page" means the text near the most prominent appearance of the work's title, preceding the beginning of the body of the text.

A section "Entitled XYZ" means a named subunit of the Document whose title either is precisely XYZ or contains XYZ in parentheses following text that translates XYZ in another language. (Here XYZ stands for a specific section name mentioned below, such as "Acknowledgements", "Dedications", "Endorsements", or "History".) To "Preserve the Title" of such a section when you modify the Document means that it remains a section "Entitled XYZ" according to this definition.

The Document may include Warranty Disclaimers next to the notice which states that this License applies to the Document. These Warranty Disclaimers are considered to be included by reference in this License, but only as regards disclaiming warranties: any other implication that these Warranty Disclaimers may have is void and has no effect on the meaning of this License.

##### 2. VERBATIM COPYING #

You may copy and distribute the Document in any medium, either commercially or non-commercially, provided that this License, the copyright notices, and the license notice saying this License applies to the Document are reproduced in all copies, and that you add no other conditions whatsoever to those of this License. You may not use technical measures to obstruct or control the reading or further copying of the copies you make or distribute. However, you may accept compensation in exchange for copies. If you distribute a large enough number of copies you must also follow the conditions in section 3.

You may also lend copies, under the same conditions stated above, and you may publicly display copies.

##### 3. COPYING IN QUANTITY #

If you publish printed copies (or copies in media that commonly have printed covers) of the Document, numbering more than 100, and the Document's license notice requires Cover Texts, you must enclose the copies in covers that carry, clearly and legibly, all these Cover Texts: Front-Cover Texts on the front cover, and Back-Cover Texts on the back cover. Both covers must also clearly and legibly identify you as the publisher of these copies. The front cover must present the full title with all words of the title equally prominent and visible. You may add other material on the covers in addition. Copying with changes limited to the covers, as long as they preserve the title of the Document and satisfy these conditions, can be treated as verbatim copying in other respects.

If the required texts for either cover are too voluminous to fit legibly, you should put the first ones listed (as many as fit reasonably) on the actual cover, and continue the rest onto adjacent pages.

If you publish or distribute Opaque copies of the Document numbering more than 100, you must either include a machine-readable Transparent copy along with each Opaque copy, or state in or with each Opaque copy a computer-network location from which the general network-using public has access to download using public-standard network protocols a complete Transparent copy of the Document, free of added material. If you use the latter option, you must take reasonably prudent steps, when you begin distribution of Opaque copies in quantity, to ensure that this Transparent copy will remain thus accessible at the stated location until at least one year after the last time you distribute an Opaque copy (directly or through your agents or retailers) of that edition to the public.

It is requested, but not required, that you contact the authors of the Document well before redistributing any large number of copies, to give them a chance to provide you with an updated version of the Document.

##### 4. MODIFICATIONS #

You may copy and distribute a Modified Version of the Document under the conditions of sections 2 and 3 above, provided that you release the Modified Version under precisely this License, with the Modified Version filling the role of the Document, thus licensing distribution and modification of the Modified Version to whoever possesses a copy of it. In addition, you must do these things in the Modified Version:

1. Use in the Title Page (and on the covers, if any) a title distinct from that of the Document, and from those of previous versions (which should, if there were any, be listed in the History section of the Document). You may use the same title as a previous version if the original publisher of that version gives permission.

2. List on the Title Page, as authors, one or more persons or entities responsible for authorship of the modifications in the Modified Version, together with at least five of the principal authors of the Document (all of its principal authors, if it has fewer than five), unless they release you from this requirement.

3. State on the Title page the name of the publisher of the Modified Version, as the publisher.

4. Preserve all the copyright notices of the Document.

5. Add an appropriate copyright notice for your modifications adjacent to the other copyright notices.

6. Include, immediately after the copyright notices, a license notice giving the public permission to use the Modified Version under the terms of this License, in the form shown in the Addendum below.

7. Preserve in that license notice the full lists of Invariant Sections and required Cover Texts given in the Document's license notice.

8. Include an unaltered copy of this License.

9. Preserve the section Entitled "History", Preserve its Title, and add to it an item stating at least the title, year, new authors, and publisher of the Modified Version as given on the Title Page. If there is no section Entitled "History" in the Document, create one stating the title, year, authors, and publisher of the Document as given on its Title Page, then add an item describing the Modified Version as stated in the previous sentence.

10. Preserve the network location, if any, given in the Document for public access to a Transparent copy of the Document, and likewise the network locations given in the Document for previous versions it was based on. These may be placed in the "History" section. You may omit a network location for a work that was published at least four years before the Document itself, or if the original publisher of the version it refers to gives permission.

11. For any section Entitled "Acknowledgements" or "Dedications", Preserve the Title of the section, and preserve in the section all the substance and tone of each of the contributor acknowledgements and/or dedications given therein.

12. Preserve all the Invariant Sections of the Document, unaltered in their text and in their titles. Section numbers or the equivalent are not considered part of the section titles.

13. Delete any section Entitled "Endorsements". Such a section may not be included in the Modified Version.

14. Do not retitle any existing section to be Entitled "Endorsements" or to conflict in title with any Invariant Section.

15. Preserve any Warranty Disclaimers.

If the Modified Version includes new front-matter sections or appendices that qualify as Secondary Sections and contain no material copied from the Document, you may at your option designate some or all of these sections as invariant. To do this, add their titles to the list of Invariant Sections in the Modified Version's license notice. These titles must be distinct from any other section titles.

You may add a section Entitled "Endorsements", provided it contains nothing but endorsements of your Modified Version by various parties--for example, statements of peer review or that the text has been approved by an organization as the authoritative definition of a standard.

You may add a passage of up to five words as a Front-Cover Text, and a passage of up to 25 words as a Back-Cover Text, to the end of the list of Cover Texts in the Modified Version. Only one passage of Front-Cover Text and one of Back-Cover Text may be added by (or through arrangements made by) any one entity. If the Document already includes a cover text for the same cover, previously added by you or by arrangement made by the same entity you are acting on behalf of, you may not add another; but you may replace the old one, on explicit permission from the previous publisher that added the old one.

The author(s) and publisher(s) of the Document do not by this License give permission to use their names for publicity for or to assert or imply endorsement of any Modified Version.

##### 5. COMBINING DOCUMENTS #

You may combine the Document with other documents released under this License, under the terms defined in section 4 above for modified versions, provided that you include in the combination all of the Invariant Sections of all of the original documents, unmodified, and list them all as Invariant Sections of your combined work in its license notice, and that you preserve all their Warranty Disclaimers.

The combined work need only contain one copy of this License, and multiple identical Invariant Sections may be replaced with a single copy. If there are multiple Invariant Sections with the same name but different contents, make the title of each such section unique by adding at the end of it, in parentheses, the name of the original author or publisher of that section if known, or else a unique number. Make the same adjustment to the section titles in the list of Invariant Sections in the license notice of the combined work.

In the combination, you must combine any sections Entitled "History" in the various original documents, forming one section Entitled "History"; likewise combine any sections Entitled "Acknowledgements", and any sections Entitled "Dedications". You must delete all sections Entitled "Endorsements".

##### 6. COLLECTIONS OF DOCUMENTS #

You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects.

You may extract a single document from such a collection, and distribute it individually under this License, provided you insert a copy of this License into the extracted document, and follow this License in all other respects regarding verbatim copying of that document.

##### 7. AGGREGATION WITH INDEPENDENT WORKS #

A compilation of the Document or its derivatives with other separate and independent documents or works, in or on a volume of a storage or distribution medium, is called an "aggregate" if the copyright resulting from the compilation is not used to limit the legal rights of the compilation's users beyond what the individual works permit. When the Document is included in an aggregate, this License does not apply to the other works in the aggregate which are not themselves derivative works of the Document.

If the Cover Text requirement of section 3 is applicable to these copies of the Document, then if the Document is less than one half of the entire aggregate, the Document's Cover Texts may be placed on covers that bracket the Document within the aggregate, or the electronic equivalent of covers if the Document is in electronic form. Otherwise they must appear on printed covers that bracket the whole aggregate.

##### 8. TRANSLATION #

Translation is considered a kind of modification, so you may distribute translations of the Document under the terms of section 4. Replacing Invariant Sections with translations requires special permission from their copyright holders, but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections. You may include a translation of this License, and all the license notices in the Document, and any Warranty Disclaimers, provided that you also include the original English version of this License and the original versions of those notices and disclaimers. In case of a disagreement between the translation and the original version of this License or a notice or disclaimer, the original version will prevail.

If a section in the Document is Entitled "Acknowledgements", "Dedications", or "History", the requirement (section 4) to Preserve its Title (section 1) will typically require changing the actual title.

##### 9. TERMINATION #

You may not copy, modify, sublicense, or distribute the Document except as expressly provided for under this License. Any other attempt to copy, modify, sublicense or distribute the Document 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.

##### 10. FUTURE REVISIONS OF THIS LICENSE #

The Free Software Foundation may publish new, revised versions of the GNU Free Documentation 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. See https://www.gnu.org/copyleft/.

Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License "or any later version" applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation.

##### ADDENDUM: How to use this License for your documents #

    Copyright (c) YEAR YOUR NAME.
    Permission is granted to copy, distribute and/or modify this document
    under the terms of the GNU Free Documentation License, Version 1.2
    or any later version published by the Free Software Foundation;
    with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
    A copy of the license is included in the section entitled “GNU
    Free Documentation License”.

If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the “with...Texts.” line with this:

    with the Invariant Sections being LIST THEIR TITLES, with the
    Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.

If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation.

If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software.