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   <section id="the-inviolable-principles-of-nuttx">
 <h1>The Inviolable Principles of NuttX<a class="headerlink" href="#the-inviolable-principles-of-nuttx" title="Permalink to this heading"></a></h1>
 <p>These are properties of NuttX that we can be certain of for all time:</p>
 <section id="definition">
 <h2>Definition<a class="headerlink" href="#definition" title="Permalink to this heading"></a></h2>
 <p><em>in·vi·o·la·ble</em>
 /inˈvīələbəl/</p>
 <p>adjective
 adjective: inviolable</p>
 <div class="highlight-none notranslate"><div class="highlight"><pre><span></span>never to be broken, infringed, or dishonored.

 &quot;an inviolable rule of chastity&quot;

 synonyms:  inalienable, absolute, untouchable, unalterable,
            unchallengeable, unbreakable, impregnable; sacrosanct,
            sacred, holy, hallowed; rare intemerate

 &quot;the inviolable right to life&quot;
 </pre></div>
 </div>
 <p>Source: Oxford Dictionary of the English Language</p>
 </section>
 <section id="strict-posix-compliance">
 <h2>Strict POSIX compliance<a class="headerlink" href="#strict-posix-compliance" title="Permalink to this heading"></a></h2>
 <ul class="simple">
 <li><p>Strict conformance to the portable standard OS interface as defined at
 OpenGroup.org.</p></li>
 <li><p>A deeply embedded system requires some special support.  Special
 support must be minimized.</p></li>
 <li><p>The portable interface must never be compromised only for the sake of
 expediency.</p></li>
 <li><p>Expediency or even improved performance are not justifications for
 violation of the strict POSIX interface.</p></li>
 </ul>
 </section>
 <section id="modular-architecture">
 <h2>Modular Architecture<a class="headerlink" href="#modular-architecture" title="Permalink to this heading"></a></h2>
 <ul class="simple">
 <li><p>The internal modular architecture of the OS must be maintained.</p></li>
 <li><p>This means formalizing and documenting all internal interfaces (in the
 porting guide), minimal use of global variables at the interface, and
 only well defined functional interfaces.</p></li>
 </ul>
 </section>
 <section id="clear-consistent-standardized-coding-style">
 <h2>Clear, Consistent, Standardized Coding Style<a class="headerlink" href="#clear-consistent-standardized-coding-style" title="Permalink to this heading"></a></h2>
 <ul>
 <li><p>Strict conformance to the NuttX coding style.  No “revolutionary”
 changes to the coding standard (but perhaps some “evolutionary”
 changes).</p></li>
 <li><p>Personal or organizational preference is not a justification for a
 coding style change.</p></li>
 <li><p>Nothing can come into NuttX that does not follow the coding standard.</p></li>
 <li><p>Expediency is not a justification for violating the coding standard.</p>
 <p>The NuttX coding standard can be found here:
 <a class="reference external" href="https://nuttx.apache.org/docs/latest/contributing/coding_style.html">https://nuttx.apache.org/docs/latest/contributing/coding_style.html</a></p>
 </li>
 </ul>
 </section>
 <section id="open-and-unencumbered-license">
 <h2>Open and Unencumbered License<a class="headerlink" href="#open-and-unencumbered-license" title="Permalink to this heading"></a></h2>
 <ul class="simple">
 <li><p>Currently BSD 3-clause or compatible:  BSD 3-clause with constraints,
 BSD 3 and 4 clause, MIT, public domain.</p></li>
 <li><p>Other unencumbered licenses such as Apache may be considered.
 NuttX will never be licensed under a restrictive, “Copyleft” license.</p></li>
 </ul>
 </section>
 <section id="all-users-matter">
 <h2>All Users Matter<a class="headerlink" href="#all-users-matter" title="Permalink to this heading"></a></h2>
 <ul class="simple">
 <li><p>All support must apply equally to all supported platforms.  At present
 this includes Linux, Windows MSYS, Windows Cygwin, Windows Ubuntu,
 Windows native, macOS, Solaris, and FreeBSD.  No tool/environment
 solutions will be considered that limit the usage of NuttX on any of
 the supported platforms.</p></li>
 <li><p>Inclusive rather than exclusive.</p></li>
 <li><p>Hobbyists are valued users of the OS including retro computing hobbyists
 and DIY “Maker” hobbyists.</p></li>
 <li><p>Supported toolchains:  GCC, Clang, SDCC, ZiLOG ZDS-II (c89), IAR.
 Others?</p></li>
 <li><p>No changes to build system should limit use of NuttX by any user.</p></li>
 <li><p>Simplifying things for one user does not justify excluding another user.</p></li>
 <li><p>We should seek to expand the NuttX user base, not to limit it for
 reasons of preference or priority.</p></li>
 <li><p>We must resist the pull to make NuttX into a Linux-only, GCC-only, and
 ARM-only solution.</p></li>
 </ul>
 </section>
 <section id="nuttx-branding">
 <h2>NuttX Branding<a class="headerlink" href="#nuttx-branding" title="Permalink to this heading"></a></h2>
 <ul class="simple">
 <li><p>The official name of authentic NuttX will always be “NuttX”.</p></li>
 <li><p>This name is trademarked and may not be used by other OSs or forks of
 NuttX.</p></li>
 </ul>
 </section>
 <section id="the-enemies">
 <h2>The Enemies<a class="headerlink" href="#the-enemies" title="Permalink to this heading"></a></h2>
 <section id="no-short-cuts">
 <h3>No Short Cuts<a class="headerlink" href="#no-short-cuts" title="Permalink to this heading"></a></h3>
 <ul class="simple">
 <li><p>Doing things the easy way instead of the correct way.</p></li>
 <li><p>Reducing effort at the expense of Quality, Portability, or
 Consistency.</p></li>
 <li><p>Focus on the values of the organization, not the values of the Open
 Source project.  Need to support both.</p></li>
 <li><p>It takes work to support the Inviolables.  There are no shortcuts.</p></li>
 </ul>
 </section>
 <section id="sometimes-code-duplication-is-ok">
 <h3>Sometimes Code Duplication is OK<a class="headerlink" href="#sometimes-code-duplication-is-ok" title="Permalink to this heading"></a></h3>
 <ul class="simple">
 <li><p>Sometimes is better to duplicate some logic than to introduce coupling.</p></li>
 </ul>
 </section>
 <section id="keep-the-big-picture">
 <h3>Keep the Big Picture<a class="headerlink" href="#keep-the-big-picture" title="Permalink to this heading"></a></h3>
 <ul class="simple">
 <li><p>Too much focus on solving the problem in hand, loss of the Big Picture.</p></li>
 <li><p>Insufficient understanding of the architectural principles.</p></li>
 </ul>
 </section>
 <section id="conform-to-standards">
 <h3>Conform to Standards<a class="headerlink" href="#conform-to-standards" title="Permalink to this heading"></a></h3>
 <ul class="simple">
 <li><p>Changing things only to suit a personal or organizational preference.</p></li>
 <li><p>Inflexibility, Inability to adapt.</p></li>
 <li><p>Not Invented Here (NIH) syndrome.</p></li>
 </ul>
 </section>
 </section>
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	<section id="the-inviolable-principles-of-nuttx">
	<h1>The Inviolable Principles of NuttX<a class="headerlink" href="#the-inviolable-principles-of-nuttx" title="Permalink to this heading"></a></h1>
	<p>These are properties of NuttX that we can be certain of for all time:</p>
	<section id="definition">
	<h2>Definition<a class="headerlink" href="#definition" title="Permalink to this heading"></a></h2>
	<p><em>in·vi·o·la·ble</em>
	/inˈvīələbəl/</p>
	<p>adjective
	adjective: inviolable</p>
	<div class="highlight-none notranslate"><div class="highlight"><pre><span></span>never to be broken, infringed, or dishonored.

	"an inviolable rule of chastity"

	synonyms: inalienable, absolute, untouchable, unalterable,
	unchallengeable, unbreakable, impregnable; sacrosanct,
	sacred, holy, hallowed; rare intemerate

	"the inviolable right to life"
	</pre></div>
	</div>
	<p>Source: Oxford Dictionary of the English Language</p>
	</section>
	<section id="strict-posix-compliance">
	<h2>Strict POSIX compliance<a class="headerlink" href="#strict-posix-compliance" title="Permalink to this heading"></a></h2>
	<ul class="simple">
	<li><p>Strict conformance to the portable standard OS interface as defined at
	OpenGroup.org.</p></li>
	<li><p>A deeply embedded system requires some special support. Special
	support must be minimized.</p></li>
	<li><p>The portable interface must never be compromised only for the sake of
	expediency.</p></li>
	<li><p>Expediency or even improved performance are not justifications for
	violation of the strict POSIX interface.</p></li>
	</ul>
	</section>
	<section id="modular-architecture">
	<h2>Modular Architecture<a class="headerlink" href="#modular-architecture" title="Permalink to this heading"></a></h2>
	<ul class="simple">
	<li><p>The internal modular architecture of the OS must be maintained.</p></li>
	<li><p>This means formalizing and documenting all internal interfaces (in the
	porting guide), minimal use of global variables at the interface, and
	only well defined functional interfaces.</p></li>
	</ul>
	</section>
	<section id="clear-consistent-standardized-coding-style">
	<h2>Clear, Consistent, Standardized Coding Style<a class="headerlink" href="#clear-consistent-standardized-coding-style" title="Permalink to this heading"></a></h2>
	<ul>
	<li><p>Strict conformance to the NuttX coding style. No “revolutionary”
	changes to the coding standard (but perhaps some “evolutionary”
	changes).</p></li>
	<li><p>Personal or organizational preference is not a justification for a
	coding style change.</p></li>
	<li><p>Nothing can come into NuttX that does not follow the coding standard.</p></li>
	<li><p>Expediency is not a justification for violating the coding standard.</p>
	<p>The NuttX coding standard can be found here:
	<a class="reference external" href="https://nuttx.apache.org/docs/latest/contributing/coding_style.html">https://nuttx.apache.org/docs/latest/contributing/coding_style.html</a></p>
	</li>
	</ul>
	</section>
	<section id="open-and-unencumbered-license">
	<h2>Open and Unencumbered License<a class="headerlink" href="#open-and-unencumbered-license" title="Permalink to this heading"></a></h2>
	<ul class="simple">
	<li><p>Currently BSD 3-clause or compatible: BSD 3-clause with constraints,
	BSD 3 and 4 clause, MIT, public domain.</p></li>
	<li><p>Other unencumbered licenses such as Apache may be considered.
	NuttX will never be licensed under a restrictive, “Copyleft” license.</p></li>
	</ul>
	</section>
	<section id="all-users-matter">
	<h2>All Users Matter<a class="headerlink" href="#all-users-matter" title="Permalink to this heading"></a></h2>
	<ul class="simple">
	<li><p>All support must apply equally to all supported platforms. At present
	this includes Linux, Windows MSYS, Windows Cygwin, Windows Ubuntu,
	Windows native, macOS, Solaris, and FreeBSD. No tool/environment
	solutions will be considered that limit the usage of NuttX on any of
	the supported platforms.</p></li>
	<li><p>Inclusive rather than exclusive.</p></li>
	<li><p>Hobbyists are valued users of the OS including retro computing hobbyists
	and DIY “Maker” hobbyists.</p></li>
	<li><p>Supported toolchains: GCC, Clang, SDCC, ZiLOG ZDS-II (c89), IAR.
	Others?</p></li>
	<li><p>No changes to build system should limit use of NuttX by any user.</p></li>
	<li><p>Simplifying things for one user does not justify excluding another user.</p></li>
	<li><p>We should seek to expand the NuttX user base, not to limit it for
	reasons of preference or priority.</p></li>
	<li><p>We must resist the pull to make NuttX into a Linux-only, GCC-only, and
	ARM-only solution.</p></li>
	</ul>
	</section>
	<section id="nuttx-branding">
	<h2>NuttX Branding<a class="headerlink" href="#nuttx-branding" title="Permalink to this heading"></a></h2>
	<ul class="simple">
	<li><p>The official name of authentic NuttX will always be “NuttX”.</p></li>
	<li><p>This name is trademarked and may not be used by other OSs or forks of
	NuttX.</p></li>
	</ul>
	</section>
	<section id="the-enemies">
	<h2>The Enemies<a class="headerlink" href="#the-enemies" title="Permalink to this heading"></a></h2>
	<section id="no-short-cuts">
	<h3>No Short Cuts<a class="headerlink" href="#no-short-cuts" title="Permalink to this heading"></a></h3>
	<ul class="simple">
	<li><p>Doing things the easy way instead of the correct way.</p></li>
	<li><p>Reducing effort at the expense of Quality, Portability, or
	Consistency.</p></li>
	<li><p>Focus on the values of the organization, not the values of the Open
	Source project. Need to support both.</p></li>
	<li><p>It takes work to support the Inviolables. There are no shortcuts.</p></li>
	</ul>
	</section>
	<section id="sometimes-code-duplication-is-ok">
	<h3>Sometimes Code Duplication is OK<a class="headerlink" href="#sometimes-code-duplication-is-ok" title="Permalink to this heading"></a></h3>
	<ul class="simple">
	<li><p>Sometimes is better to duplicate some logic than to introduce coupling.</p></li>
	</ul>
	</section>
	<section id="keep-the-big-picture">
	<h3>Keep the Big Picture<a class="headerlink" href="#keep-the-big-picture" title="Permalink to this heading"></a></h3>
	<ul class="simple">
	<li><p>Too much focus on solving the problem in hand, loss of the Big Picture.</p></li>
	<li><p>Insufficient understanding of the architectural principles.</p></li>
	</ul>
	</section>
	<section id="conform-to-standards">
	<h3>Conform to Standards<a class="headerlink" href="#conform-to-standards" title="Permalink to this heading"></a></h3>
	<ul class="simple">
	<li><p>Changing things only to suit a personal or organizational preference.</p></li>
	<li><p>Inflexibility, Inability to adapt.</p></li>
	<li><p>Not Invented Here (NIH) syndrome.</p></li>
	</ul>
	</section>
	</section>
	</section>


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