fixes #514 Need documentation updates for 1.0

7 files changed, 876 insertions, 47 deletions

diff --git a/README.adoc b/README.adoc
index bac1683c..db63cf90 100644
--- a/README.adoc
+++ b/README.adoc
@@ -1,44 +1,135 @@
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-:tip-caption: :bulb:
 :note-caption: :information_source:
 :important-caption: :heavy_exclamation_mark:
-:caution-caption: :fire:
-:warning-caption: :warning:
 endif::[]
 = nng - nanomsg-next-gen
 
+// Note: This README is optimized for display with Asciidoctor, or
+// on the github status page.  An HTML version is in the same directory
+// and may be more pleasantly formatted for human readers (when opened
+// in a browswer).
+
+// Note: If you're updating this file, don't forget to re-run asciidoctor
+// to update the aforementioned HTML file!
+
 image:https://img.shields.io/badge/license-MIT-blue.svg[MIT License]
 image:https://img.shields.io/circleci/project/github/nanomsg/nng.svg?label=[Linux Status,link="https://circleci.com/gh/nanomsg/nng"]
 image:https://img.shields.io/appveyor/ci/nanomsg/nng/master.svg?label=windows[Windows Status,link="https://ci.appveyor.com/project/nanomsg/nng"]
 image:https://codecov.io/gh/nanomsg/nng/branch/master/graph/badge.svg?label=coverage[Coverage,link="https://codecov.io/gh/nanomsg/nng"]
 image:https://api.codacy.com/project/badge/Grade/f241cba192974787b66f7e4368777ebf["Codacy code quality", link="https://www.codacy.com/app/gdamore/nng?utm_source=github.com&utm_medium=referral&utm_content=nanomsg/nng&utm_campaign=Badge_Grade"]
 
-This repository represents a rewrite of the SP protocol
-library known as https://github.com/nanomsg/nanomsg[libnanomsg].
 
-This is pre-release, but at this point we believe that the library is
-robust enough to use for development and testing, and we are actively
-seeing additional testing and review.
+NOTE: If you are looking for the legacy version of nanomsg, please
+see the https://github.com/nanomsg/nanomsg[nanomsg] repository.
+
+This project is a rewrite of the Scalability Protocols
+library known as https://github.com/nanomsg/nanomsg[libnanomsg],
+and adds significant new capabilities, while retaining
+compatibility with the original.
+
+It may help to think of this as "nanomsg-next-generation".
+
+== NNG: Lightweight Messaging Library
+
+NNG, like its predecessors http://nanomsg.org[nanomsg] (and to some extent
+http://zeromq.org/[ZeroMQ]), is a lightweight, brokerless library,
+offering a simple API to solve common recurring messaging problems,
+such as publish/subscribe, RPC-style request/reply, or service discovery.
+The API frees the programmer from worrying about details like connection
+management, retries, and other comomon considerations, so that they
+can focus on the application instead of the plumbing.
+
+NNG is implemented in C, requiring only C99 and CMake to build.
+It can be built as a shared or a static library, and is readily
+embeddable.  It is also designed to be easy to port to new platforms
+if your platform is not already supported.
+
+== License
+
+NNG is licensed under a liberal, and commercial friendly, MIT license.
+The goal to the license is to minimize friction in adoption, use, and
+contribution.
+
+== Enhancements (Relative to nanomsg)
+
+Here are areas where this project improves on "nanomsg":
+
+[horizontal]
+*Reliability*:: NNG is designed for production use from the beginning.  Every
+error case is considered, and it is designed to avoid crashing except in cases
+of gross developer error.  (Hopefully we don't have any of these in our own
+code.)
+
+*Scalability*:: NNG scales out to engage multiple cores using a bespoke
+asynchronous I/O framework, using thread pools to spread load without
+exceeding typical system limits.
+
+*Maintainability*:: NNG's architecture is designed to be modular and
+easily grasped by developers unfamiliar with the code base.  The code
+is also well documented.
+
+*Extensibility*:: Because it avoids ties to file descriptors, and avoids
+confusing interlocking state machines, it is easier to add new protocols
+and transports to NNG.  This was demonstrated by the addition of the
+TLS and ZeroTier transports.
 
-While we have made every reasonable effort to ensure that this library
-is robust and safe, it is still a *pre-release*, and details are subject
-to change.  Caution is advised before depending upon it.
+*Security*:: NNG provides TLS 1.2 and ZeroTier transports, offering
+support for robust and industry standard authentication and encryption.
+In addition, it is hardened to be resilient against malicious attackers,
+with special consideration given to use in a hostile Internet.
 
-NOTE: We're getting pretty close to removing this caveat though,
-and we'd like help from others in testing to further improve our confidence
-before we do.
+*Usability*:: NNG eschews slavish adherence parts of the more complex and
+less well understood POSIX APIs, while adopting the semantics that are
+familiar and useful.  New APIs are intuitive, and the optional support
+for separating protocol context and state from sockets makes creating
+concurrent applications vastly simpler than previously possible.
 
-When the library is ready for broader consumption, an
-announcement will be posted on the nanomsg mailing list and website.
+== Compatibility
 
-If you are looking for the current production version of nanomsg, please
-see the https://github.com/nanomsg/nanomsg[nanomsg repo].
+This project offers both wire compatibility and API compability,
+so most nanomsg users can begin using NNG right away.
 
-If you want to build and test yourself, you need CMake version 3.1, and
-you can use standard CMake build recipes.  (We highly recommend using
-https://ninja-build.org[Ninja] as it is much faster than traditional
-build systems.) On a Linux/UNIX system, if you have Ninja already
-installed, you can for example do:
+Existing nanomsg and github.com/go-mangos/mangos[mangos] applications
+can interoperate with NNG applications automatically.
+
+That said, there are some areas where legacy nanomsg still offers
+capabilities NNG lacks -- specifically enhanced observability with
+statistics, and tunable prioritization of different destinations
+are missing, but will be added in a future release.
+
+Additionally, some API capabilities that are useful for foreign
+language bindings are not implemented yet.
+
+Some simple single threaded, synchronous applications may perform better under
+legacy nanomsg than under NNG.  (We believe that these applications are the
+least commonly deployed, and least interesting from a performance perspective.
+NNG's internal design is slightly less efficient in such scenarios, but it
+greatly benefits when concurrency or when multiple sockets or network peers
+are involved.)
+
+== Supported Platforms
+
+NNG supports Linux, macOS, Windows (Vista or better), illumos, Solaris,
+FreeBSD, Android, and iOS.  Most other POSIX platforms should work out of
+the box but have not been tested.  Very old versions of otherwise supported
+platforms might not work.
+
+== Requirements
+
+To build this project, you will need a C99 compatible compiler and
+http://www.cmake.org[CMake] version 3.1 or newer.
+
+We recommend using the https://ninja-build.org[Ninja] build
+system (pass "-G Ninja" to CMake) when you can.
+(And not just because Ninja sounds like "NNG" -- it's also
+blindingly fast and has made our lives as developers measurably better.)
+
+If you want to build with TLS support you will also need
+https://tls.mbed.org[mbedTLS].  Seee <<docs/BUILD_TLS.adoc#>> for details.
+
+== Quick Start
+
+With a Linux or UNIX environment:
 
 [source,sh]
 ----
@@ -48,33 +139,38 @@ installed, you can for example do:
   $ ninja test
 ----
 
-This library can be compiled with support for TLS, which enables
-the use of the "tls+tcp://" and "wss://" schemes.  In order to this,
-configure with `-DNNG_ENABLE_TLS=ON`.
+== API Documentation
+
+The API documentation is provided in Asciidoc format in the
+`docs/man` subdirectory, and also
+https://nanomsg.github.io/nng[online].
+The <<docs/man/libnng.3.adoc#,libnng(3)>> page is a good starting point.
 
-NOTE: The `NNG_ENABLE_TLS` library depends on the ARM
-https://tls.mbed.org[mbedTLS] library.  This library is available
-in packaged form for many systems, and can be built for just about
-any of the others.  However, please be aware of the licensing
-implications, because the mbedTLS library carries other licensing
-requirements (either Apache or GPL) than _nng_.
-either Apache or GPL licenses.
+You can also purchase a copy of the 
+http://staysail.tech/books/nng_reference/index.html[__NNG Reference Manual__].
+(It is published in both electronic and printed formats.)
+Purchases of the book help fund continued development of NNG.
 
-Much of the library, but not all, is documented in the docs/ folder,
-and also https://nanomsg.github.io/nng[online].
+== Example Programs
 
-You can also buy a copy of the 
-https://leanpub.com/nngmanual/[NNG Reference Manual at Leanpub].
-(Purchases from Leanpub help fund our work, and get get a nicer
-formatted single PDF or ebook edition.)
+Some demonstration programs have been created to help serve as examples.
+These are located in the `demo` directory.
 
-You can also explore the `nng.h` header file, which provides the public
-API. A legacy compatible `nng_compat.h` header is available and
-offers API compatibility with legacy _nanomsg_.
+== Legacy Compatibility
+
+A legacy libnanomsg compatible API is available, and while it offers
+less capability than the modern NNG API, it may serve as a transition aid.
+Please see <<docs/man/nng_compat.3compat.adoc#,nng_compat(3)>> for details.
 
 == Commercial Support
 
-Commercial support for _NNG_ is available.
+Commercial support for NNG is available.
 
 Please contact mailto:info@staysail.tech[Staysail Systems, Inc.] to
 inquire further.
+
+== Commercial Sponsors
+
+The development of NNG has been made possible through the generous
+sponsorship of https://www.capitar.com[Capitar IT Group BV] and
+http://staysail.tech[Staysail Systems, Inc.].
diff --git a/README.html b/README.html
new file mode 100644
index 00000000..f2d99b5c
--- /dev/null
+++ b/README.html
@@ -0,0 +1,715 @@
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+<body class="article">
+<div id="header">
+<h1>nng - nanomsg-next-gen</h1>
+</div>
+<div id="content">
+<div id="preamble">
+<div class="sectionbody">
+<div class="paragraph">
+<p><span class="image"><img src="https://img.shields.io/badge/license-MIT-blue.svg" alt="MIT License"></span>
+<span class="image"><a class="image" href="https://circleci.com/gh/nanomsg/nng"><img src="https://img.shields.io/circleci/project/github/nanomsg/nng.svg?label=" alt="Linux Status"></a></span>
+<span class="image"><a class="image" href="https://ci.appveyor.com/project/nanomsg/nng"><img src="https://img.shields.io/appveyor/ci/nanomsg/nng/master.svg?label=windows" alt="Windows Status"></a></span>
+<span class="image"><a class="image" href="https://codecov.io/gh/nanomsg/nng"><img src="https://codecov.io/gh/nanomsg/nng/branch/master/graph/badge.svg?label=coverage" alt="Coverage"></a></span>
+<span class="image"><a class="image" href="https://www.codacy.com/app/gdamore/nng?utm_source=github.com&amp;utm_medium=referral&amp;utm_content=nanomsg/nng&amp;utm_campaign=Badge_Grade"><img src="https://api.codacy.com/project/badge/Grade/f241cba192974787b66f7e4368777ebf" alt="Codacy code quality"></a></span></p>
+</div>
+<div class="admonitionblock note">
+<table>
+<tr>
+<td class="icon">
+<div class="title">Note</div>
+</td>
+<td class="content">
+If you are looking for the legacy version of nanomsg, please
+see the <a href="https://github.com/nanomsg/nanomsg">nanomsg</a> repository.
+</td>
+</tr>
+</table>
+</div>
+<div class="paragraph">
+<p>This project is a rewrite of the Scalability Protocols
+library known as <a href="https://github.com/nanomsg/nanomsg">libnanomsg</a>,
+and adds significant new capabilities, while retaining
+compatibility with the original.</p>
+</div>
+<div class="paragraph">
+<p>It may help to think of this as "nanomsg-next-generation".</p>
+</div>
+</div>
+</div>
+<div class="sect1">
+<h2 id="_nng_lightweight_messaging_library">NNG: Lightweight Messaging Library</h2>
+<div class="sectionbody">
+<div class="paragraph">
+<p>NNG, like its predecessors <a href="http://nanomsg.org">nanomsg</a> (and to some extent
+<a href="http://zeromq.org/">ZeroMQ</a>), is a lightweight, brokerless library,
+offering a simple API to solve common recurring messaging problems,
+such as publish/subscribe, RPC-style request/reply, or service discovery.
+The API frees the programmer from worrying about details like connection
+management, retries, and other comomon considerations, so that they
+can focus on the application instead of the plumbing.</p>
+</div>
+<div class="paragraph">
+<p>NNG is implemented in C, requiring only C99 and CMake to build.
+It can be built as a shared or a static library, and is readily
+embeddable.  It is also designed to be easy to port to new platforms
+if your platform is not already supported.</p>
+</div>
+</div>
+</div>
+<div class="sect1">
+<h2 id="_license">License</h2>
+<div class="sectionbody">
+<div class="paragraph">
+<p>NNG is licensed under a liberal, and commercial friendly, MIT license.
+The goal to the license is to minimize friction in adoption, use, and
+contribution.</p>
+</div>
+</div>
+</div>
+<div class="sect1">
+<h2 id="_enhancements_relative_to_nanomsg">Enhancements (Relative to nanomsg)</h2>
+<div class="sectionbody">
+<div class="paragraph">
+<p>Here are areas where this project improves on "nanomsg":</p>
+</div>
+<div class="hdlist">
+<table>
+<tr>
+<td class="hdlist1">
+<strong>Reliability</strong>
+</td>
+<td class="hdlist2">
+<p>NNG is designed for production use from the beginning.  Every
+error case is considered, and it is designed to avoid crashing except in cases
+of gross developer error.  (Hopefully we don&#8217;t have any of these in our own
+code.)</p>
+</td>
+</tr>
+<tr>
+<td class="hdlist1">
+<strong>Scalability</strong>
+</td>
+<td class="hdlist2">
+<p>NNG scales out to engage multiple cores using a bespoke
+asynchronous I/O framework, using thread pools to spread load without
+exceeding typical system limits.</p>
+</td>
+</tr>
+<tr>
+<td class="hdlist1">
+<strong>Maintainability</strong>
+</td>
+<td class="hdlist2">
+<p>NNG&#8217;s architecture is designed to be modular and
+easily grasped by developers unfamiliar with the code base.  The code
+is also well documented.</p>
+</td>
+</tr>
+<tr>
+<td class="hdlist1">
+<strong>Extensibility</strong>
+</td>
+<td class="hdlist2">
+<p>Because it avoids ties to file descriptors, and avoids
+confusing interlocking state machines, it is easier to add new protocols
+and transports to NNG.  This was demonstrated by the addition of the
+TLS and ZeroTier transports.</p>
+</td>
+</tr>
+<tr>
+<td class="hdlist1">
+<strong>Security</strong>
+</td>
+<td class="hdlist2">
+<p>NNG provides TLS 1.2 and ZeroTier transports, offering
+support for robust and industry standard authentication and encryption.
+In addition, it is hardened to be resilient against malicious attackers,
+with special consideration given to use in a hostile Internet.</p>
+</td>
+</tr>
+<tr>
+<td class="hdlist1">
+<strong>Usability</strong>
+</td>
+<td class="hdlist2">
+<p>NNG eschews slavish adherence parts of the more complex and
+less well understood POSIX APIs, while adopting the semantics that are
+familiar and useful.  New APIs are intuitive, and the optional support
+for separating protocol context and state from sockets makes creating
+concurrent applications vastly simpler than previously possible.</p>
+</td>
+</tr>
+</table>
+</div>
+</div>
+</div>
+<div class="sect1">
+<h2 id="_compatibility">Compatibility</h2>
+<div class="sectionbody">
+<div class="paragraph">
+<p>This project offers both wire compatibility and API compability,
+so most nanomsg users can begin using NNG right away.</p>
+</div>
+<div class="paragraph">
+<p>Existing nanomsg and github.com/go-mangos/mangos[mangos] applications
+can interoperate with NNG applications automatically.</p>
+</div>
+<div class="paragraph">
+<p>That said, there are some areas where legacy nanomsg still offers
+capabilities NNG lacks&#8201;&#8212;&#8201;specifically enhanced observability with
+statistics, and tunable prioritization of different destinations
+are missing, but will be added in a future release.</p>
+</div>
+<div class="paragraph">
+<p>Additionally, some API capabilities that are useful for foreign
+language bindings are not implemented yet.</p>
+</div>
+<div class="paragraph">
+<p>Some simple single threaded, synchronous applications may perform better under
+legacy nanomsg than under NNG.  (We believe that these applications are the
+least commonly deployed, and least interesting from a performance perspective.
+NNG&#8217;s internal design is slightly less efficient in such scenarios, but it
+greatly benefits when concurrency or when multiple sockets or network peers
+are involved.)</p>
+</div>
+</div>
+</div>
+<div class="sect1">
+<h2 id="_supported_platforms">Supported Platforms</h2>
+<div class="sectionbody">
+<div class="paragraph">
+<p>NNG supports Linux, macOS, Windows (Vista or better), illumos, Solaris,
+FreeBSD, Android, and iOS.  Most other POSIX platforms should work out of
+the box but have not been tested.  Very old versions of otherwise supported
+platforms might not work.</p>
+</div>
+</div>
+</div>
+<div class="sect1">
+<h2 id="_requirements">Requirements</h2>
+<div class="sectionbody">
+<div class="paragraph">
+<p>To build this project, you will need a C99 compatible compiler and
+<a href="http://www.cmake.org">CMake</a> version 3.1 or newer.</p>
+</div>
+<div class="paragraph">
+<p>We recommend using the <a href="https://ninja-build.org">Ninja</a> build
+system (pass "-G Ninja" to CMake) when you can.
+(And not just because Ninja sounds like "NNG"&#8201;&#8212;&#8201;it&#8217;s also
+blindingly fast and has made our lives as developers measurably better.)</p>
+</div>
+<div class="paragraph">
+<p>If you want to build with TLS support you will also need
+<a href="https://tls.mbed.org">mbedTLS</a>.  Seee <a href="docs/BUILD_TLS.html">docs/BUILD_TLS.html</a> for details.</p>
+</div>
+</div>
+</div>
+<div class="sect1">
+<h2 id="_quick_start">Quick Start</h2>
+<div class="sectionbody">
+<div class="paragraph">
+<p>With a Linux or UNIX environment:</p>
+</div>
+<div class="listingblock">
+<div class="content">
+<pre class="highlight"><code class="language-sh" data-lang="sh">  $ mkdir build
+  $ cmake -G Ninja ..
+  $ ninja
+  $ ninja test</code></pre>
+</div>
+</div>
+</div>
+</div>
+<div class="sect1">
+<h2 id="_api_documentation">API Documentation</h2>
+<div class="sectionbody">
+<div class="paragraph">
+<p>The API documentation is provided in Asciidoc format in the
+<code>docs/man</code> subdirectory, and also
+<a href="https://nanomsg.github.io/nng">online</a>.
+The <a href="docs/man/libnng.3.html">libnng(3)</a> page is a good starting point.</p>
+</div>
+<div class="paragraph">
+<p>You can also purchase a copy of the
+<a href="http://staysail.tech/books/nng_reference/index.html"><em>NNG Reference Manual</em></a>.
+(It is published in both electronic and printed formats.)
+Purchases of the book help fund continued development of NNG.</p>
+</div>
+</div>
+</div>
+<div class="sect1">
+<h2 id="_example_programs">Example Programs</h2>
+<div class="sectionbody">
+<div class="paragraph">
+<p>Some demonstration programs have been created to help serve as examples.
+These are located in the <code>demo</code> directory.</p>
+</div>
+</div>
+</div>
+<div class="sect1">
+<h2 id="_legacy_compatibility">Legacy Compatibility</h2>
+<div class="sectionbody">
+<div class="paragraph">
+<p>A legacy libnanomsg compatible API is available, and while it offers
+less capability than the modern NNG API, it may serve as a transition aid.
+Please see <a href="docs/man/nng_compat.3compat.html">nng_compat(3)</a> for details.</p>
+</div>
+</div>
+</div>
+<div class="sect1">
+<h2 id="_commercial_support">Commercial Support</h2>
+<div class="sectionbody">
+<div class="paragraph">
+<p>Commercial support for NNG is available.</p>
+</div>
+<div class="paragraph">
+<p>Please contact <a href="mailto:info@staysail.tech">Staysail Systems, Inc.</a> to
+inquire further.</p>
+</div>
+</div>
+</div>
+<div class="sect1">
+<h2 id="_commercial_sponsors">Commercial Sponsors</h2>
+<div class="sectionbody">
+<div class="paragraph">
+<p>The development of NNG has been made possible through the generous
+sponsorship of <a href="https://www.capitar.com">Capitar IT Group BV</a> and
+<a href="http://staysail.tech">Staysail Systems, Inc.</a>.</p>
+</div>
+</div>
+</div>
+</div>
+<div id="footer">
+<div id="footer-text">
+Last updated 2018-06-08 11:35:28 PDT
+</div>
+</div>
+</body>
+</html>
\ No newline at end of file
diff --git a/docs/BUILD_ANDROID.adoc b/docs/BUILD_ANDROID.adoc
index 6e210c6d..7cb40339 100644
--- a/docs/BUILD_ANDROID.adoc
+++ b/docs/BUILD_ANDROID.adoc
@@ -1,7 +1,10 @@
+ifdef::env-github[]
+:note-caption: :information_source:
+endif::[]
+
 = Building for Android
 
-NOTE: I am not an Android developer, so this work has received only cursory
-testing.  As always, _caveat emptor_.
+NOTE: This work has received only cursory testing.  As always, _caveat emptor_.
 
 == Pre-Requisites
 
diff --git a/docs/BUILD_CROSSCOMPILE.adoc b/docs/BUILD_CROSSCOMPILE.adoc
index 8b57f812..c943f173 100644
--- a/docs/BUILD_CROSSCOMPILE.adoc
+++ b/docs/BUILD_CROSSCOMPILE.adoc
@@ -1,3 +1,7 @@
+ifdef::env-github[]
+:note-caption: :information_source:
+endif::[]
+
 = Building for Cross Compilation
 
 TIP: Cross-compiling is used when the operating system or process architecure
diff --git a/docs/BUILD_IOS.adoc b/docs/BUILD_IOS.adoc
index eed23714..80f7c906 100644
--- a/docs/BUILD_IOS.adoc
+++ b/docs/BUILD_IOS.adoc
@@ -1,7 +1,10 @@
+ifdef::env-github[]
+:note-caption: :information_source:
+endif::[]
+
 = Building for iOS (and tvOS, watchOS)
 
-NOTE: I am not an iOS developer, so this work has had only minimal validation.
-As always, _caveat emptor_!
+NOTE: This work has had only minimal validation.  As always, _caveat emptor_.
 
 == Pre-Requisites
 
diff --git a/docs/BUILD_TLS.adoc b/docs/BUILD_TLS.adoc
index 242e7f44..0ffa9c9d 100644
--- a/docs/BUILD_TLS.adoc
+++ b/docs/BUILD_TLS.adoc
@@ -1,3 +1,7 @@
+ifdef::env-github[]
+:important-caption: :heavy_exclamation_mark:
+endif::[]
+
 = Building for TLSv1.2 Support
 
 If you want to include support for Transport Layer Security
diff --git a/docs/BUILD_ZEROTIER.adoc b/docs/BUILD_ZEROTIER.adoc
index 28f6098d..a61d065c 100644
--- a/docs/BUILD_ZEROTIER.adoc
+++ b/docs/BUILD_ZEROTIER.adoc
@@ -1,3 +1,7 @@
+ifdef::env-github[]
+:important-caption: :heavy_exclamation_mark:
+endif::[]
+
 = Building for ZeroTier Support
 
 If you want to include support for the experimental ZeroTier