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<h2>Table of Contents</h2>
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<li><span class="stability_undefined"><a href="#documentation_about_this_documentation">About this Documentation</a></span><ul>
<li><span class="stability_undefined"><a href="#documentation_contributing">Contributing</a></span></li>
<li><span class="stability_undefined"><a href="#documentation_stability_index">Stability Index</a></span></li>
<li><span class="stability_1"><a href="#documentation_json_output">JSON Output</a></span></li>
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<h1>About this Documentation<span><a class="mark" href="#documentation_about_this_documentation"id="documentation_about_this_documentation">#</a></span></h1>
<!--introduced_in=v0.10.0-->
<!-- type=misc -->
<p>The goal of this documentation is to comprehensively explain the Node.js
API, both from a reference as well as a conceptual point of view. Each
section describes a built-in module or high-level concept.</p>
<p>Where appropriate, property types, method arguments, and the arguments
provided to event handlers are detailed in a list underneath the topic
heading.</p>
<h2>Contributing<span><a class="mark" href="#documentation_contributing"id="documentation_contributing">#</a></span></h2>
<p>If you find an error in this documentation, please <a href="https://github.com/nodejs/node/issues/new">submit an issue</a>
or see <a href="https://github.com/nodejs/node/blob/master/CONTRIBUTING.md">the contributing guide</a> for directions on how to submit a patch.</p>
<p>Every file is generated based on the corresponding <code>.md</code> file in the
<code>doc/api/</code> folder in Node.js's source tree. The documentation is generated
using the <code>tools/doc/generate.js</code> program. An HTML template is located at
<code>doc/template.html</code>.</p>
<h2>Stability Index<span><a class="mark" href="#documentation_stability_index"id="documentation_stability_index">#</a></span></h2>
<!--type=misc-->
<p>Throughout the documentation, you will see indications of a section's
stability. The Node.js API is still somewhat changing, and as it
matures, certain parts are more reliable than others. Some are so
proven, and so relied upon, that they are unlikely to ever change at
all. Others are brand new and experimental, or known to be hazardous
and in the process of being redesigned.</p>
<p>The stability indices are as follows:</p>
<div class="api_stability api_stability_0"><a href="documentation.html#documentation_stability_index">Stability: 0</a> - Deprecated This feature is known to be problematic, and changes may be planned. Do not rely on it. Use of the feature may cause warnings to be emitted. Backwards compatibility across major versions should not be expected.</div><div class="api_stability api_stability_1"><a href="documentation.html#documentation_stability_index">Stability: 1</a> - Experimental This feature is still under active development and subject to non-backwards compatible changes, or even removal, in any future version. Use of the feature is not recommended in production environments. Experimental features are not subject to the Node.js Semantic Versioning model.</div><div class="api_stability api_stability_2"><a href="documentation.html#documentation_stability_index">Stability: 2</a> - Stable The API has proven satisfactory. Compatibility with the npm ecosystem is a high priority, and will not be broken unless absolutely necessary.</div><p><em>Note</em>: Caution must be used when making use of <code>Experimental</code> features,
particularly within modules that may be used as dependencies (or dependencies
of dependencies) within a Node.js application. End users may not be aware that
experimental features are being used, and therefore may experience unexpected
failures or behavior changes when API modifications occur. To help avoid such
surprises, <code>Experimental</code> features may require a command-line flag to
explicitly enable them, or may cause a process warning to be emitted.
By default, such warnings are printed to <a href="process.html#process_process_stderr"><code>stderr</code></a> and may be handled by
attaching a listener to the <a href="process.html#process_event_warning"><code>process.on('warning')</code></a> event.</p>
<h2>JSON Output<span><a class="mark" href="#documentation_json_output"id="documentation_json_output">#</a></span></h2>
<div class="api_metadata">
<span>Added in: v0.6.12</span>
</div><div class="api_stability api_stability_1"><a href="documentation.html#documentation_stability_index">Stability: 1</a> - Experimental</div><p>Every <code>.html</code> document has a corresponding <code>.json</code> document presenting
the same information in a structured manner. This feature is
experimental, and added for the benefit of IDEs and other utilities that
wish to do programmatic things with the documentation.</p>
<h2>Syscalls and man pages<span><a class="mark" href="#documentation_syscalls_and_man_pages"id="documentation_syscalls_and_man_pages">#</a></span></h2>
<p>System calls like <a href="http://man7.org/linux/man-pages/man2/open.2.html">open(2)</a> and <a href="http://man7.org/linux/man-pages/man2/read.2.html">read(2)</a> define the interface between user programs
and the underlying operating system. Node functions which simply wrap a syscall,
like <a href="fs.html#fs_fs_open_path_flags_mode_callback"><code>fs.open()</code></a>, will document that. The docs link to the corresponding man
pages (short for manual pages) which describe how the syscalls work.</p>
<p>Some syscalls, like <a href="http://man7.org/linux/man-pages/man2/lchown.2.html">lchown(2)</a>, are BSD-specific. That means, for
example, that <a href="fs.html#fs_fs_lchown_path_uid_gid_callback"><code>fs.lchown()</code></a> only works on macOS and other BSD-derived systems,
and is not available on Linux.</p>
<p>Most Unix syscalls have Windows equivalents, but behavior may differ on Windows
relative to Linux and macOS. For an example of the subtle ways in which it's
sometimes impossible to replace Unix syscall semantics on Windows, see <a href="https://github.com/nodejs/node/issues/4760">Node
issue 4760</a>.</p>
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