1NODE(1) BSD General Commands Manual NODE(1)
2
4 node — server-side JavaScript runtime
5
7 node [options] [v8-options] [-e string | script.js | -] [--]
8 [arguments ...]
9 node inspect [-e string | script.js | - | <host>:<port>] ...
10 node [--v8-options]
11
13 Node.js is a set of libraries for JavaScript which allows it to be used
14 outside of the browser. It is primarily focused on creating simple,
15 easy-to-build network clients and servers.
16 Execute node without arguments to start a REPL.
18
20 - Alias for stdin, analogous to the use of - in other command-line
21 utilities. The executed script is read from stdin, and remaining
22 arguments are passed to the script.
23 -- Indicate the end of command-line options. Pass the rest of the
25 arguments to the script.
26 If no script filename or eval/print script is supplied prior to
28 this, then the next argument will be used as a script filename.
29 --abort-on-uncaught-exception
31 Aborting instead of exiting causes a core file to be generated
32 for analysis.
33 --completion-bash
35 Print source-able bash completion script for Node.js.
36 -C, --conditions string
38 Use custom conditional exports conditions. string
39 --cpu-prof
41 Start the V8 CPU profiler on start up, and write the CPU profile
42 to disk before exit. If --cpu-prof-dir is not specified, the pro‐
43 file will be written to the current working directory with a gen‐
44 erated file name.
45 --cpu-prof-dir
47 The directory where the CPU profiles generated by --cpu-prof will
48 be placed. The default value is controlled by the
49 --diagnostic-dir. command-line option.
50 --cpu-prof-interval
52 The sampling interval in microseconds for the CPU profiles gener‐
53 ated by --cpu-prof. The default is 1000.
54 --cpu-prof-name
56 File name of the V8 CPU profile generated with --cpu-prof.
57 --diagnostic-dir
59 Set the directory for all diagnostic output files. Default is
60 current working directory. Set the directory to which all diag‐
61 nostic output files will be written to. Defaults to current
62 working directory. Affects the default output directory of:
63 --cpu-prof-dir. --heap-prof-dir. --redirect-warnings.
64 --disable-proto=mode
66 Disable the `Object.prototype.__proto__` property. If mode is
67 `delete`, the property will be removed entirely. If mode is
68 `throw`, accesses to the property will throw an exception with
69 the code `ERR_PROTO_ACCESS`.
70 --disallow-code-generation-from-strings
72 Make built-in language features like `eval` and `new Function`
73 that generate code from strings throw an exception instead. This
74 does not affect the Node.js `vm` module.
75 --enable-fips
77 Enable FIPS-compliant crypto at startup. Requires Node.js to be
78 built with ./configure --openssl-fips.
79 --enable-source-maps
81 Enable Source Map V3 support for stack traces.
82 --experimental-import-meta-resolve
84 Enable experimental ES modules support for import.meta.resolve().
85 --experimental-json-modules
87 Enable experimental JSON interop support for the ES Module
88 loader.
89 --experimental-loader=module
91 Specify the module to use as a custom module loader.
92 --experimental-policy
94 Use the specified file as a security policy.
95 --no-experimental-repl-await
97 Disable top-level await keyword support in REPL.
98 --experimental-specifier-resolution
100 Select extension resolution algorithm for ES Modules; either 'ex‐
101 plicit' (default) or 'node'.
102 --experimental-vm-modules
104 Enable experimental ES module support in VM module.
105 --experimental-wasi-unstable-preview1
107 Enable experimental WebAssembly System Interface support.
108 --experimental-wasm-modules
110 Enable experimental WebAssembly module support.
111 --force-context-aware
113 Disable loading native addons that are not context-aware.
114 --force-fips
116 Force FIPS-compliant crypto on startup (Cannot be disabled from
117 script code). Same requirements as --enable-fips.
118 --frozen-intrinsics
120 Enable experimental frozen intrinsics support.
121 --heapsnapshot-near-heap-limit=max_count
123 Generate heap snapshot when the V8 heap usage is approaching the
124 heap limit. No more than the specified number of snapshots will
125 be generated.
126 --heapsnapshot-signal=signal
128 Generate heap snapshot on specified signal.
129 --heap-prof
131 Start the V8 heap profiler on start up, and write the heap pro‐
132 file to disk before exit. If --heap-prof-dir is not specified,
133 the profile will be written to the current working directory with
134 a generated file name.
135 --heap-prof-dir
137 The directory where the heap profiles generated by --heap-prof
138 will be placed. The default value is controlled by the
139 --diagnostic-dir. command-line option.
140 --heap-prof-interval
142 The average sampling interval in bytes for the heap profiles gen‐
143 erated by --heap-prof. The default is 512 * 1024.
144 --heap-prof-name
146 File name of the V8 heap profile generated with --heap-prof.
147 --icu-data-dir=file
149 Specify ICU data load path. Overrides NODE_ICU_DATA.
150 --input-type=type
152 Set the module resolution type for input via --eval, --print or
153 STDIN.
154 --inspect-brk=[host:]port
156 Activate inspector on host:port and break at start of user
157 script.
158 --inspect-port=[host:]port
160 Set the host:port to be used when the inspector is activated.
161 --inspect-publish-uid=stderr,http
163 Specify how the inspector WebSocket URL is exposed. Valid values
164 are stderr and http. Default is stderr,http.
165 --inspect=[host:]port
167 Activate inspector on host:port. Default is 127.0.0.1:9229.
168 V8 Inspector integration allows attaching Chrome DevTools and
170 IDEs to Node.js instances for debugging and profiling. It uses
171 the Chrome DevTools Protocol.
172 --insecure-http-parser
174 Use an insecure HTTP parser that accepts invalid HTTP headers.
175 This may allow interoperability with non-conformant HTTP imple‐
176 mentations. It may also allow request smuggling and other HTTP
177 attacks that rely on invalid headers being accepted. Avoid using
178 this option.
179 --jitless
181 Disable runtime allocation of executable memory. This may be re‐
182 quired on some platforms for security reasons. It can also reduce
183 attack surface on other platforms, but the performance impact may
184 be severe.
185 This flag is inherited from V8 and is subject to change upstream.
187 It may disappear in a non-semver-major release.
188 --max-http-header-size=size
190 Specify the maximum size of HTTP headers in bytes. Defaults to 16
191 KB.
192 --napi-modules
194 This option is a no-op. It is kept for compatibility.
195 --no-deprecation
197 Silence deprecation warnings.
198 --no-force-async-hooks-checks
200 Disable runtime checks for `async_hooks`. These will still be
201 enabled dynamically when `async_hooks` is enabled.
202 --no-addons
204 Disable the `node-addons` exports condition as well as disable
205 loading native addons. When `--no-addons` is specified, calling
206 `process.dlopen` or requiring a native C++ addon will fail and
207 throw an exception.
208 --no-global-search-paths
210 Do not search modules from global paths.
211 --no-warnings
213 Silence all process warnings (including deprecations).
214 --node-memory-debug
216 Enable extra debug checks for memory leaks in Node.js internals.
217 This is usually only useful for developers debugging Node.js it‐
218 self.
219 --openssl-config=file
221 Load an OpenSSL configuration file on startup. Among other uses,
222 this can be used to enable FIPS-compliant crypto if Node.js is
223 built with ./configure --openssl-fips.
224 --pending-deprecation
226 Emit pending deprecation warnings.
227 --policy-integrity=sri
229 Instructs Node.js to error prior to running any code if the pol‐
230 icy does not have the specified integrity. It expects a Subre‐
231 source Integrity string as a parameter.
232 --preserve-symlinks
234 Instructs the module loader to preserve symbolic links when re‐
235 solving and caching modules other than the main module.
236 --preserve-symlinks-main
238 Instructs the module loader to preserve symbolic links when re‐
239 solving and caching the main module.
240 --prof Generate V8 profiler output.
242 --prof-process
244 Process V8 profiler output generated using the V8 option --prof.
245 --redirect-warnings=file
247 Write process warnings to the given file instead of printing to
248 stderr.
249 --report-compact
251 Write diagnostic reports in a compact format, single-line JSON.
252 --report-dir --report-directory
254 Location at which the diagnostic report will be generated. The
255 `file` name may be an absolute path. If it is not, the default
256 directory it will be written to is controlled by the
257 --diagnostic-dir. command-line option.
258 --report-filename
260 Name of the file to which the diagnostic report will be written.
261 --report-on-fatalerror
263 Enables the diagnostic report to be triggered on fatal errors
264 (internal errors within the Node.js runtime such as out of mem‐
265 ory) that leads to termination of the application. Useful to in‐
266 spect various diagnostic data elements such as heap, stack, event
267 loop state, resource consumption etc. to reason about the fatal
268 error.
269 --report-on-signal
271 Enables diagnostic report to be generated upon receiving the
272 specified (or predefined) signal to the running Node.js process.
273 Default signal is SIGUSR2.
274 --report-signal
276 Sets or resets the signal for diagnostic report generation (not
277 supported on Windows). Default signal is SIGUSR2.
278 --report-uncaught-exception
280 Enables diagnostic report to be generated on un-caught excep‐
281 tions. Useful when inspecting JavaScript stack in conjunction
282 with native stack and other runtime environment data.
283 --secure-heap=n
285 Specify the size of the OpenSSL secure heap. Any value less than
286 2 disables the secure heap. The default is 0. The value must be a
287 power of two.
288 --secure-heap-min=n
290 Specify the minimum allocation from the OpenSSL secure heap. The
291 default is 2. The value must be a power of two.
292 --throw-deprecation
294 Throw errors for deprecations.
295 --title=title
297 Specify process.title on startup.
298 --tls-cipher-list=list
300 Specify an alternative default TLS cipher list. Requires Node.js
301 to be built with crypto support. (Default)
302 --tls-keylog=file
304 Log TLS key material to a file. The key material is in NSS SS‐
305 LKEYLOGFILE format and can be used by software (such as Wire‐
306 shark) to decrypt the TLS traffic.
307 --tls-max-v1.2
309 Set default maxVersion to 'TLSv1.2'. Use to disable support for
310 TLSv1.3.
311 --tls-max-v1.3
313 Set default maxVersion to 'TLSv1.3'. Use to enable support for
314 TLSv1.3.
315 --tls-min-v1.0
317 Set default minVersion to 'TLSv1'. Use for compatibility with old
318 TLS clients or servers.
319 --tls-min-v1.1
321 Set default minVersion to 'TLSv1.1'. Use for compatibility with
322 old TLS clients or servers.
323 --tls-min-v1.2
325 Set default minVersion to 'TLSv1.2'. This is the default for 12.x
326 and later, but the option is supported for compatibility with
327 older Node.js versions.
328 --tls-min-v1.3
330 Set default minVersion to 'TLSv1.3'. Use to disable support for
331 TLSv1.2 in favour of TLSv1.3, which is more secure.
332 --trace-atomics-wait
334 Print short summaries of calls to Atomics.wait().
335 --trace-deprecation
337 Print stack traces for deprecations.
338 --trace-event-categories categories
340 A comma-separated list of categories that should be traced when
341 trace event tracing is enabled using --trace-events-enabled.
342 --trace-event-file-pattern pattern
344 Template string specifying the filepath for the trace event data,
345 it supports ${rotation} and ${pid}.
346 --trace-events-enabled
348 Enable the collection of trace event tracing information.
349 --trace-exit
351 Prints a stack trace whenever an environment is exited proac‐
352 tively, i.e. invoking `process.exit()`.
353 --trace-sigint
355 Prints a stack trace on SIGINT.
356 --trace-sync-io
358 Print a stack trace whenever synchronous I/O is detected after
359 the first turn of the event loop.
360 --trace-tls
362 Prints TLS packet trace information to stderr.
363 --trace-uncaught
365 Print stack traces for uncaught exceptions; usually, the stack
366 trace associated with the creation of an Error is printed,
367 whereas this makes Node.js also print the stack trace associated
368 with throwing the value (which does not need to be an Error in‐
369 stance).
370 Enabling this option may affect garbage collection behavior nega‐
372 tively.
373 --trace-warnings
375 Print stack traces for process warnings (including deprecations).
376 --track-heap-objects
378 Track heap object allocations for heap snapshots.
379 --unhandled-rejections=mode
381 Define the behavior for unhandled rejections. Can be one of
382 `strict` (raise an error), `warn` (enforce warnings) or `none`
383 (silence warnings).
384 --use-bundled-ca, --use-openssl-ca
386 Use bundled Mozilla CA store as supplied by current Node.js ver‐
387 sion or use OpenSSL's default CA store. The default store is se‐
388 lectable at build-time.
389 The bundled CA store, as supplied by Node.js, is a snapshot of
391 Mozilla CA store that is fixed at release time. It is identical
392 on all supported platforms.
393 Using OpenSSL store allows for external modifications of the
395 store. For most Linux and BSD distributions, this store is main‐
396 tained by the distribution maintainers and system administrators.
397 OpenSSL CA store location is dependent on configuration of the
398 OpenSSL library but this can be altered at runtime using environ‐
399 ment variables.
400 See SSL_CERT_DIR and SSL_CERT_FILE.
402 --use-largepages=mode
404 Re-map the Node.js static code to large memory pages at startup.
405 If supported on the target system, this will cause the Node.js
406 static code to be moved onto 2 MiB pages instead of 4 KiB pages.
407 mode must have one of the following values: `off` (the default
409 value, meaning do not map), `on` (map and ignore failure, report‐
410 ing it to stderr), or `silent` (map and silently ignore failure).
411 --v8-options
413 Print V8 command-line options.
414 --v8-pool-size=num
416 Set V8's thread pool size which will be used to allocate back‐
417 ground jobs. If set to 0 then V8 will choose an appropriate size
418 of the thread pool based on the number of online processors. If
419 the value provided is larger than V8's maximum, then the largest
420 value will be chosen.
421 --zero-fill-buffers
423 Automatically zero-fills all newly allocated Buffer and Slow‐
424 Buffer instances.
425 -c, --check
427 Check the script's syntax without executing it. Exits with an
428 error code if script is invalid.
429 -e, --eval string
431 Evaluate string as JavaScript.
432 -h, --help
434 Print command-line options. The output of this option is less
435 detailed than this document.
436 -i, --interactive
438 Open the REPL even if stdin does not appear to be a terminal.
439 -p, --print string
441 Identical to -e, but prints the result.
442 -r, --require module
444 Preload the specified module at startup. Follows `require()`'s
445 module resolution rules. module may be either a path to a file,
446 or a Node.js module name.
447 -v, --version
449 Print node's version.
450
452 FORCE_COLOR
453 Used to enable ANSI colorized output. The value may be one of: 1
454 , true , or an empty string to indicate 16-color support, 2 to
455 indicate 256-color support, or 3 to indicate 16 million-color
456 support. When used and set to a supported value, both the
457 NO_COLOR and NODE_DISABLE_COLORS environment variables are ig‐
458 nored. Any other value will result in colorized output being dis‐
459 abled.
460 NO_COLOR
462 Alias for NODE_DISABLE_COLORS
463 NODE_DEBUG modules...
465 Comma-separated list of core modules that should print debug in‐
466 formation.
467 NODE_DEBUG_NATIVE modules...
469 Comma-separated list of C++ core modules that should print debug
470 information.
471 NODE_DISABLE_COLORS
473 When set to 1, colors will not be used in the REPL.
474 NODE_EXTRA_CA_CERTS file
476 When set, the well-known “root” CAs (like VeriSign) will be ex‐
477 tended with the extra certificates in file. The file should con‐
478 sist of one or more trusted certificates in PEM format.
479 If file is missing or misformatted, a message will be emitted
481 once using process.emitWarning(), but any errors are otherwise
482 ignored.
483 This environment variable is ignored when `node` runs as setuid
485 root or has Linux file capabilities set.
486 The NODE_EXTRA_CA_CERTS environment variable is only read when
488 the Node.js process is first launched. Changing the value at
489 runtime using process.env.NODE_EXTRA_CA_CERTS has no effect on
490 the current process.
491 NODE_ICU_DATA file
493 Data path for ICU (Intl object) data. Will extend linked-in data
494 when compiled with small-icu support.
495 NODE_NO_WARNINGS
497 When set to 1, process warnings are silenced.
498 NODE_OPTIONS options...
500 A space-separated list of command-line options, which are inter‐
501 preted as if they had been specified on the command line before
502 the actual command (so they can be overridden). Node.js will
503 exit with an error if an option that is not allowed in the envi‐
504 ronment is used, such as --print or a script file.
505 NODE_PATH directories...
507 A colon-separated list of directories prefixed to the module
508 search path.
509 NODE_PENDING_DEPRECATION
511 When set to 1, emit pending deprecation warnings.
512 NODE_PRESERVE_SYMLINKS
514 When set to 1, the module loader preserves symbolic links when
515 resolving and caching modules.
516 NODE_REDIRECT_WARNINGS file
518 Write process warnings to the given file instead of printing to
519 stderr. Equivalent to passing --redirect-warnings file on the
520 command line.
521 NODE_REPL_HISTORY file
523 Path to the file used to store persistent REPL history. The de‐
524 fault path is ~/.node_repl_history, which is overridden by this
525 variable. Setting the value to an empty string ("" or " ") will
526 disable persistent REPL history.
527 NODE_SKIP_PLATFORM_CHECK
529 When set to 1, the check for a supported platform is skipped dur‐
530 ing Node.js startup. Node.js might not execute correctly. Any
531 issues encountered on unsupported platforms will not be fixed.
532 NODE_TLS_REJECT_UNAUTHORIZED
534 When set to 0, TLS certificate validation is disabled.
535 NODE_V8_COVERAGE dir
537 When set, Node.js writes JavaScript code coverage information to
538 dir.
539 OPENSSL_CONF file
541 Load an OpenSSL configuration file on startup. Among other uses,
542 this can be used to enable FIPS-compliant crypto if Node.js is
543 built with ./configure --openssl-fips.
544 If the --openssl-config command-line option is used, this envi‐
546 ronment variable is ignored.
547 SSL_CERT_DIR dir
549 If --use-openssl-ca is enabled, this overrides and sets OpenSSL's
550 directory containing trusted certificates.
551 SSL_CERT_FILE file
553 If --use-openssl-ca is enabled, this overrides and sets OpenSSL's
554 file containing trusted certificates.
555 UV_THREADPOOL_SIZE size
557 Sets the number of threads used in libuv's threadpool to size.
558
560 Bugs are tracked in GitHub Issues: https://github.com/nodejs/node/issues
561
563 Copyright Node.js contributors. Node.js is available under the MIT li‐
564 cense.
565 Node.js also includes external libraries that are available under a vari‐
567 ety of licenses. See https://github.com/nodejs/node/blob/HEAD/LICENSE
568 for the full license text.
569
571 Website: https://nodejs.org/
572 Documentation: https://nodejs.org/api/
574 GitHub repository and issue tracker: https://github.com/nodejs/node
576 IRC (general questions): libera.chat #node.js (unofficial)
578
580 Written and maintained by 1000+ contributors:
581 https://github.com/nodejs/node/blob/HEAD/AUTHORS
582 December 5, 2021