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