doc: environment variables

doc/main.h

@@ -2,6 +2,7 @@
  * \file
  * Main page of the Doxygen-generated documentation.
  */
+
 /**
  * \mainpage ns-3 Documentation
  *
@@ -70,6 +71,7 @@
  *     - wimax
  *
  */
+
 /**
  * \namespace ns3
  * \brief Every class exported by the ns3 library is enclosed in the
@@ -107,3 +109,12 @@
 #define NS3_LOG_ENABLE
 
 /**@}*/
+
+/**
+ * \page EnvironVar All Environment Variables
+ *
+ * All environment variables used by ns-3 are documented by module.
+ *
+ * \section environcore Core Enviroment Variables
+ * See \ref core-environ
+ */

src/core/doc/core.h

@@ -81,3 +81,19 @@
  * \defgroup core-tests Core module tests
  * TestSuites for the Core module
  */
+
+/**
+ * \ingroup core
+ * \defgroup system System Services
+ *
+ * System-independent interfaces to operating system services:
+ * environment variables, files system, threading, wall clock time.
+ *
+ * Services provided:
+ *
+ *   - Environment variables
+ *   - File and directory paths.
+ *   - Thread primitives:  threads, conditional waits, mutex, critical sections.
+ *   - Asynchronous input from a file descriptor.
+ *   - Wall clock time.
+ */

src/core/doc/environment-variables.h

@@ -0,0 +1,189 @@
+/*
+ * Copyright (c) 2022 Lawrence Livermore National Laboratory
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation;
+ *
+ * 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
+ *
+ * Author: Peter D. Barnes, Jr. <pdbarnes@llnl.gov>
+ */
+
+// This file supplies Doxygen documentation only.
+// It should *NOT* be included in the build.
+
+/**
+ * \ingroup system
+ * \defgroup core-environ Environment Variables
+ */
+
+/**
+ * \ingroup core-environ
+ * \brief Initialize an ns3::Attribute
+ *
+ * Sets a new default \pname{value} for an Attribute.
+ * This is invoked if the ns3::Object being constructed has an Attribute
+ * matching \pname{name}, and that Attribute didn't appear in the
+ * ns3::AttributeConstructionList argument to ns3::ObjectBase::ConstructSelf.
+ * The ns3::AttributeConstructionList is typically createad by an ns3::ObjectFactory
+ * and populated by ns3::ObjectFactory::Set.
+ *
+ * All objects with an Attribute matching \pname{name} will be matched,
+ * so name collisions could wreak havoc.
+ *
+ * <dl class="params">
+ *   <dt>%Parameters</dt>
+ *     <dd>
+ *       <table class="params">
+ *         <tr>
+ *           <td class="paramname">name</td>
+ *           <td>The name of the Attribute to set.</td>
+ *         </tr>
+ *         <tr>
+ *           <td class="paramname">value</td>
+ *           <td>The value to set the Attribute to.</td>
+ *         </tr>
+ *         <tr>
+ *           <td class="paramname">;</td>
+ *           <td>Multiple \pname{name}=\pname{value} pairs should be delimited by ';'</td>
+ *         </tr>
+ *       </table>
+ *     </dd>
+ * </dl>
+ *
+ * Referenced by ns3::ObjectBase::ConstructSelf.
+ */
+const char* NS_ATTRIBUTE_DEFAULT = "name=value[;...]";
+
+/**
+ * \ingroup core-environ
+ * \brief Write the ns3::CommandLine::Usage message, in Doxygen format,
+ * to the referenced location.
+ *
+ * Set the directory where ns3::CommandLine instances should write their Usage
+ * message, used when building documentation.
+ *
+ * This is used primarily by the documentation builds, which execute each
+ * registered example to gather their ns3::CommmandLine::Usage information.
+ * This wouldn't normally be useful to users.
+ *
+ * <dl class="params">
+ *   <dt>%Parameters</dt>
+ *   <dd>
+ *     <table class="params">
+ *       <tr>
+ *         <td class="paramname">path</td>
+ *         <td> The directory where ns3::CommandLine should write its Usage message.</td>
+ *       </tr>
+ *     </table>
+ *   </dd>
+ * </dl>
+ *
+ * Referenced by ns3::CommandLine::PrintDoxygenUsage.
+ */
+const char* NS_COMMANDLINE_INTROSPECTION = "path";
+
+/**
+ * \ingroup core-environ
+ * \brief Initialize a ns3::GlobalValue.
+ *
+ * Initialize the ns3::GlobalValue \pname{name} from \pname{value}.
+ *
+ * This overrides the initial value set in the corresponding
+ * ns3::GlobalValue constructor.
+ *
+ * <dl class="params">
+ *   <dt>%Parameters</dt>
+ *   <dd>
+ *     <table class="params">
+ *       <tr>
+ *         <td class="paramname">name</td>
+ *         <td>The name of the ns3::GlobalValue to set.</td>
+ *       </tr>
+ *       <tr>
+ *         <td class="paramname">value</td>
+ *         <td>The value to set the ns3::GlobalValue to.</td>
+ *       </tr>
+ *       <tr>
+ *         <td class="paramname">;</td>
+ *         <td>Multiple \pname{name}=\pname{value} pairs should be delimited by ';'</td>
+ *       </tr>
+ *     </table>
+ *   </dd>
+ * </dl>
+ *
+ * Referenced by ns3::GlobalValue::InitializeFromEnv.
+ */
+const char* NS_GLOBAL_VALUE = "name=value[;...]";
+
+/**
+ * \ingroup core-environ
+ * \brief Control which logging components are enabled.
+ *
+ * Enable logging from specific \pname{component}s, with specified \pname{option}s.
+ * See the \ref logging module, or the Logging chapter
+ * in the manual for details on what symbols can be used for specifying
+ * log level and prefix options.
+ *
+ * <dl class="params">
+ *   <dt>%Parameters</dt>
+ *   <dd>
+ *     <table class="params">
+ *       <tr>
+ *         <td class="paramname">component</td>
+ *         <td>The logging component to enable.</td>
+ *       </tr>
+ *       <tr>
+ *         <td class="paramname">option</td>
+ *         <td>Log level and or prefix to enable. Multiple options should be delimited with '|'</td>
+ *       </tr>
+ *       <tr>
+ *         <td class="paramname">:</td>
+ *         <td>Multiple logging components can be enabled simultaneously, delimited by ':'</td>
+ *       </tr>
+ *     </table>
+ *   </dd>
+ * </dl>
+ *
+ * Referenced by ns3::PrintList, ns3::LogComponent::EnvVarCheck and
+ * ns3::CheckEnvironmentVariables(), all in \ref log.cc.
+ */
+const char* NS_LOG = "component=option[|option...][:...]";
+
+/**
+ * \ingroup core-environ
+ * \brief Where to make temporary directories.
+ *
+ * The absolute path where ns-3 should make temporary directories.
+ *
+ * See ns3::SystemPath::MakeTemporaryDirectoryName for details on how this environment
+ * variable is used to create a temporary directory, and how that directory
+ * will be named.
+ *
+ * <dl class="params">
+ *   <dt>%Parameters</dt>
+ *   <dd>
+ *     <table class="params">
+ *       <tr>
+ *         <td class="paramname">path</td>
+ *         <td>The absolute path in which to create the temporary directory.</td>
+ *       </tr>
+ *     </table>
+ *   </dd>
+ * </dl>
+ *
+ * Referenced by ns3::SystemPath::MakeTemporaryDirectoryName.
+ *
+ * @{
+ */
+const char* TMP = "path";
+const char* TEMP = "path";
+/**@}*/