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href="#documentation_stability_overview">Stability overview</a></li> 151<li><a href="#documentation_json_output">JSON output</a></li> 152<li><a href="#documentation_system_calls_and_man_pages">System calls and man pages</a></li> 153</ul> 154</li> 155</ul></details> 156 157 <div id="apicontent"> 158 <h2>About this documentation<span><a class="mark" href="#documentation_about_this_documentation" id="documentation_about_this_documentation">#</a></span></h2> 159 160 161<p>Welcome to the official API reference documentation for Node.js!</p> 162<p>Node.js is a JavaScript runtime built on the <a href="https://v8.dev/">V8 JavaScript engine</a>.</p> 163<section><h3>Contributing<span><a class="mark" href="#documentation_contributing" id="documentation_contributing">#</a></span></h3> 164<p>Report errors in this documentation in <a href="https://github.com/nodejs/node/issues/new">the issue tracker</a>. See 165<a href="https://github.com/nodejs/node/blob/HEAD/CONTRIBUTING.md">the contributing guide</a> for directions on how to submit pull requests.</p> 166</section><section><h3>Stability index<span><a class="mark" href="#documentation_stability_index" id="documentation_stability_index">#</a></span></h3> 167 168<p>Throughout the documentation are indications of a section's stability. Some APIs 169are so proven and so relied upon that they are unlikely to ever change at all. 170Others are brand new and experimental, or known to be hazardous.</p> 171<p>The stability indices are as follows:</p> 172<p></p><div class="api_stability api_stability_0">Stability: 0 - Deprecated. The feature may emit warnings. Backward 173compatibility is not guaranteed.</div><p></p> 174<!-- separator --> 175<p></p><div class="api_stability api_stability_1">Stability: 1 - Experimental. The feature is not subject to 176<a href="https://semver.org/">Semantic Versioning</a> rules. Non-backward compatible changes or removal may 177occur in any future release. Use of the feature is not recommended in 178production environments.</div><p></p> 179<!-- separator --> 180<p></p><div class="api_stability api_stability_2">Stability: 2 - Stable. Compatibility with the npm ecosystem is a high 181priority.</div><p></p> 182<!-- separator --> 183<p></p><div class="api_stability api_stability_3">Stability: 3 - Legacy. The feature is no longer recommended for use. While it 184likely will not be removed, and is still covered by semantic-versioning 185guarantees, use of the feature should be avoided.</div><p></p> 186<p>Use caution when making use of Experimental features, particularly within 187modules. Users may not be aware that experimental features are being used. 188Bugs or behavior changes may surprise users when Experimental API 189modifications occur. To avoid surprises, use of an Experimental feature may need 190a command-line flag. Experimental features may also emit a <a href="process.html#process_event_warning">warning</a>.</p> 191</section><section><h3>Stability overview<span><a class="mark" href="#documentation_stability_overview" id="documentation_stability_overview">#</a></span></h3> 192<!-- STABILITY_OVERVIEW_SLOT_BEGIN --><table><thead><tr><th>API</th><th>Stability</th></tr></thead><tbody><tr><td class="module_stability"><a href="assert.html">assert</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="async_hooks.html">async_hooks</a></td><td class="api_stability api_stability_1">(1) Experimental</td></tr><tr><td class="module_stability"><a href="buffer.html">buffer</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="child_process.html">child_process</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="cluster.html">cluster</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="console.html">console</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="crypto.html">crypto</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="dgram.html">dgram</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="diagnostics_channel.html">diagnostics_channel</a></td><td class="api_stability api_stability_1">(1) Experimental</td></tr><tr><td class="module_stability"><a href="dns.html">dns</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="domain.html">domain</a></td><td class="api_stability api_stability_0">(0) Deprecated</td></tr><tr><td class="module_stability"><a href="fs.html">fs</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="http.html">http</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="http2.html">http/2</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="https.html">https</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="inspector.html">inspector</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="modules.html">module</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="os.html">os</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="path.html">path</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="perf_hooks.html">performance_measurement_apis</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="punycode.html">punycode</a></td><td class="api_stability api_stability_0">(0) Deprecated</td></tr><tr><td class="module_stability"><a href="querystring.html">querystring</a></td><td class="api_stability api_stability_3">(3) Legacy</td></tr><tr><td class="module_stability"><a href="readline.html">readline</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="repl.html">repl</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="stream.html">stream</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="string_decoder.html">string_decoder</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="timers.html">timers</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="tls.html">tls_(ssl)</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="tracing.html">trace_events</a></td><td class="api_stability api_stability_1">(1) Experimental</td></tr><tr><td class="module_stability"><a href="tty.html">tty</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="url.html">url</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="util.html">util</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="vm.html">vm</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="wasi.html">webassembly_system_interface_(wasi)</a></td><td class="api_stability api_stability_1">(1) Experimental</td></tr><tr><td class="module_stability"><a href="worker_threads.html">worker_threads</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr><tr><td class="module_stability"><a href="zlib.html">zlib</a></td><td class="api_stability api_stability_2">(2) Stable</td></tr></tbody></table><!-- STABILITY_OVERVIEW_SLOT_END --> 193</section><section><h3>JSON output<span><a class="mark" href="#documentation_json_output" id="documentation_json_output">#</a></span></h3> 194<div class="api_metadata"> 195<span>Added in: v0.6.12</span> 196</div> 197<p>Every <code>.html</code> document has a corresponding <code>.json</code> document. This is for IDEs 198and other utilities that consume the documentation.</p> 199</section><section><h3>System calls and man pages<span><a class="mark" href="#documentation_system_calls_and_man_pages" id="documentation_system_calls_and_man_pages">#</a></span></h3> 200<p>Node.js functions which wrap a system call will document that. The docs link 201to the corresponding man pages which describe how the system call works.</p> 202<p>Most Unix system calls have Windows analogues. Still, behavior differences may 203be unavoidable.</p></section> 204 <!-- API END --> 205 </div> 206 </div> 207 </div> 208 <script> 209 'use strict'; 210 { 211 const kCustomPreference = 'customDarkTheme'; 212 const userSettings = sessionStorage.getItem(kCustomPreference); 213 const themeToggleButton = document.getElementById('theme-toggle-btn'); 214 if (userSettings === null && window.matchMedia) { 215 const mq = window.matchMedia('(prefers-color-scheme: dark)'); 216 if ('onchange' in mq) { 217 function mqChangeListener(e) { 218 document.body.classList.toggle('dark-mode', e.matches); 219 } 220 mq.addEventListener('change', mqChangeListener); 221 if (themeToggleButton) { 222 themeToggleButton.addEventListener('click', function() { 223 mq.removeEventListener('change', mqChangeListener); 224 }, { once: true }); 225 } 226 } 227 if (mq.matches) { 228 document.body.classList.add('dark-mode'); 229 } 230 } else if (userSettings === 'true') { 231 document.body.classList.add('dark-mode'); 232 } 233 if (themeToggleButton) { 234 themeToggleButton.hidden = false; 235 themeToggleButton.addEventListener('click', function() { 236 sessionStorage.setItem( 237 kCustomPreference, 238 document.body.classList.toggle('dark-mode') 239 ); 240 }); 241 } 242 } 243 </script> 244</body> 245</html> 246