js (1) - Linux Manuals

js: server-side JavaScript runtime

NAME

node - server-side JavaScript runtime

SYNOPSIS

node [options ] [v8-options ] [-e string | script.js | - ] [- ] [arguments ... ]
node inspect [-e string | script.js | -| <host>:<port> ] ...
node [--v8-options ]

DESCRIPTION

Node.js is a set of libraries for JavaScript which allows it to be used outside of the browser. It is primarily focused on creating simple, easy-to-build network clients and servers.

Execute node without arguments to start a REPL.

OPTIONS

-
Alias for stdin, analogous to the use of - in other command-line utilities. The executed script is read from stdin, and remaining arguments are passed to the script.
-
Indicate the end of command-line options. Pass the rest of the arguments to the script.

If no script filename or eval/print script is supplied prior to this, then the next argument will be used as a script filename.

--abort-on-uncaught-exception
Aborting instead of exiting causes a core file to be generated for analysis.
--completion-bash
Print source-able bash completion script for Node.js.
--enable-fips
Enable FIPS-compliant crypto at startup. Requires Node.js to be built with ./configure --openssl-fips
--experimental-modules
Enable experimental ES module support and caching modules.
--experimental-repl-await
Enable experimental top-level await keyword support in REPL.
--experimental-vm-modules
Enable experimental ES module support in VM module.
--experimental-worker
Enable experimental worker threads using worker_threads module.
--force-fips
Force FIPS-compliant crypto on startup (Cannot be disabled from script code). Same requirements as --enable-fips
--http-parser = library
Chooses an HTTP parser library. Available values are llhttp or legacy
--icu-data-dir = file
Specify ICU data load path. Overrides NODE_ICU_DATA
--inspect-brk = [host:]port
Activate inspector on host:port and break at start of user script.
--inspect-port = [host:]port
Set the host:port to be used when the inspector is activated.
--inspect = [host:]port
Activate inspector on host:port Default is 127.0.0.1:9229

V8 Inspector integration allows attaching Chrome DevTools and IDEs to Node.js instances for debugging and profiling. It uses the Chrome DevTools Protocol.

--loader = file
Specify the file as a custom loader, to load --experimental-modules
--insecure-http-parser
Use an insecure HTTP parser that accepts invalid HTTP headers. This may allow interoperability with non-conformant HTTP implementations. It may also allow request smuggling and other HTTP attacks that rely on invalid headers being accepted. Avoid using this option.
--max-http-header-size = size
Specify the maximum size of HTTP headers in bytes. Defaults to 8KB.
--napi-modules
This option is a no-op. It is kept for compatibility.
--no-deprecation
Silence deprecation warnings.
--no-force-async-hooks-checks
Disable runtime checks for `async_hooks`. These will still be enabled dynamically when `async_hooks` is enabled.
--no-warnings
Silence all process warnings (including deprecations).
--openssl-config = file
Load an OpenSSL configuration file on startup. Among other uses, this can be used to enable FIPS-compliant crypto if Node.js is built with ./configure --openssl-fips
--pending-deprecation
Emit pending deprecation warnings.
--preserve-symlinks
Instructs the module loader to preserve symbolic links when resolving and caching modules other than the main module.
--preserve-symlinks-main
Instructs the module loader to preserve symbolic links when resolving and caching the main module.
--prof
Generate V8 profiler output.
--prof-process
Process V8 profiler output generated using the V8 option --prof
--redirect-warnings = file
Write process warnings to the given file instead of printing to stderr.
--throw-deprecation
Throw errors for deprecations.
--title = title
Specify process.title on startup.
--tls-cipher-list = list
Specify an alternative default TLS cipher list. Requires Node.js to be built with crypto support. (Default)
--trace-deprecation
Print stack traces for deprecations.
--trace-event-categories categories
A comma-separated list of categories that should be traced when trace event tracing is enabled using --trace-events-enabled
--trace-event-file-pattern pattern
Template string specifying the filepath for the trace event data, it supports ${rotation} and ${pid}
--trace-events-enabled
Enable the collection of trace event tracing information.
--trace-sync-io
Print a stack trace whenever synchronous I/O is detected after the first turn of the event loop.
--trace-warnings
Print stack traces for process warnings (including deprecations).
--track-heap-objects
Track heap object allocations for heap snapshots.
---unhandled-rejections=mode
Define the behavior for unhandled rejections. Can be one of `strict` (raise an error), `warn` (enforce warnings) or `none` (silence warnings).
--use-bundled-ca , --use-openssl-ca
Use bundled Mozilla CA store as supplied by current Node.js version or use OpenSSL's default CA store. The default store is selectable at build-time.

The bundled CA store, as supplied by Node.js, is a snapshot of Mozilla CA store that is fixed at release time. It is identical on all supported platforms.

Using OpenSSL store allows for external modifications of the store. For most Linux and BSD distributions, this store is maintained by the distribution maintainers and system administrators. OpenSSL CA store location is dependent on configuration of the OpenSSL library but this can be altered at runtime using environment variables.

See SSL_CERT_DIR and SSL_CERT_FILE

--v8-options
Print V8 command-line options.
--v8-pool-size = num
Set V8's thread pool size which will be used to allocate background jobs. If set to 0 then V8 will choose an appropriate size of the thread pool based on the number of online processors. If the value provided is larger than V8's maximum, then the largest value will be chosen.
--zero-fill-buffers
Automatically zero-fills all newly allocated Buffer and SlowBuffer instances.
-c , --check
Check the script's syntax without executing it. Exits with an error code if script is invalid.
-e , --eval string
Evaluate string as JavaScript.
-h , --help
Print command-line options. The output of this option is less detailed than this document.
-i , --interactive
Open the REPL even if stdin does not appear to be a terminal.
-p , --print string
Identical to -e but prints the result.
-r , --require module
Preload the specified module at startup. Follows `require()`'s module resolution rules. module may be either a path to a file, or a Node.js module name.
-v , --version
Print node's version.

ENVIRONMENT

NODE_DEBUG modules...
Comma-separated list of core modules that should print debug information.
NODE_DEBUG_NATIVE modules...
Comma-separated list of C++ core modules that should print debug information.
NODE_DISABLE_COLORS
When set to 1 colors will not be used in the REPL.
NODE_EXTRA_CA_CERTS file
When set, the well-known ``root'' CAs (like VeriSign) will be extended with the extra certificates in file The file should consist of one or more trusted certificates in PEM format.

If file is missing or misformatted, a message will be emitted once using process.emitWarning() but any errors are otherwise ignored.

This environment variable is ignored when `node` runs as setuid root or has Linux file capabilities set.

NODE_ICU_DATA file
Data path for ICU (Intl object) data. Will extend linked-in data when compiled with small-icu support.
NODE_NO_WARNINGS
When set to 1 process warnings are silenced.
NODE_OPTIONS options...
A space-separated list of command-line options which are interpreted as if they had been specified on the command-line before the actual command (so they can be overridden). Node.js will exit with an error if an option that is not allowed in the environment is used, such as --print or a script file.
NODE_PATH directories...
A colon-separated list of directories prefixed to the module search path.
NODE_PENDING_DEPRECATION
When set to 1 emit pending deprecation warnings.
NODE_PRESERVE_SYMLINKS
When set to 1 the module loader preserves symbolic links when resolving and caching modules.
NODE_REDIRECT_WARNINGS file
Write process warnings to the given file instead of printing to stderr. Equivalent to passing --redirect-warnings file on command-line.
NODE_REPL_HISTORY file
Path to the file used to store persistent REPL history. The default path is ~/.node_repl_history which is overridden by this variable. Setting the value to an empty string ("" or " ") will disable persistent REPL history.
NODE_TLS_REJECT_UNAUTHORIZED
When set to 0 TLS certificate validation is disabled.
NODE_V8_COVERAGE dir
When set, Node.js writes JavaScript code coverage information to dir
OPENSSL_CONF file
Load an OpenSSL configuration file on startup. Among other uses, this can be used to enable FIPS-compliant crypto if Node.js is built with ./configure --openssl-fips

If the --openssl-config command-line option is used, this environment variable is ignored.

SSL_CERT_DIR dir
If --use-openssl-ca is enabled, this overrides and sets OpenSSL's directory containing trusted certificates.
SSL_CERT_FILE file
If --use-openssl-ca is enabled, this overrides and sets OpenSSL's file containing trusted certificates.
UV_THREADPOOL_SIZE size
Sets the number of threads used in libuv's threadpool to size

BUGS

Bugs are tracked in GitHub Issues: https://github.com/nodejs/node/issues

COPYRIGHT

Copyright Node.js contributors. Node.js is available under the MIT license.

Node.js also includes external libraries that are available under a variety of licenses. See https://github.com/nodejs/node/blob/master/LICENSE for the full license text.

AUTHORS

Written and maintained by 1000+ contributors: https://github.com/nodejs/node/blob/master/AUTHORS

SEE ALSO

Website: https://nodejs.org/

Documentation: https://nodejs.org/api/

GitHub repository & Issue Tracker: https://github.com/nodejs/node

IRC (general questions): chat.freenode.net #node.js (unofficial)

IRC (Node.js core development): chat.freenode.net #node-dev