Node.js (1)

- About these Docs
- Synopsis
- Assertion Testing
- Buffer
- C/C++ Addons
- Child Processes
- Cluster
- Console
- Crypto
- Debugger
- DNS
- Domain
- Errors
- Events
- File System
- Globals
- HTTP
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- Modules
- Net
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- Path
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- Punycode
- Query Strings
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- Stream
- String Decoder
- Timers
- TLS/SSL
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- URL
- Utilities
- V8
- VM
- ZLIB

# Global Objects#

These objects are available in all modules. Some of these objects aren't actually in the global scope but in the module scope - this will be noted.

## global#

- {Object} The global namespace object.

In browsers, the top-level scope is the global scope. That means that in browsers if you're in the global scope `var something` will define a global variable. In Node.js this is different. The top-level scope is not the global scope; `var something` inside an Node.js module will be local to that module.

## process#

- {Object}

The process object. See the process object section.

## console#

- {Object}

Used to print to stdout and stderr. See the console section.

## Class: Buffer#

- {Function}

Used to handle binary data. See the buffer section

## require()#

- {Function}

To require modules. See the Modules section. `require` isn't actually a global but rather local to each module.

### require.resolve()#

Use the internal `require()` machinery to look up the location of a module, but rather than loading the module, just return the resolved filename.

### require.cache#

- Object

Modules are cached in this object when they are required. By deleting a key value from this object, the next `require` will reload the module.

### require.extensions#

    Stability: 0 - Deprecated

- Object

Instruct `require` on how to handle certain file extensions.

Process files with the extension `.sjs` as `.js`:

    require.extensions['.sjs'] = require.extensions['.js'];

Deprecated In the past, this list has been used to load non-JavaScript modules into Node.js by compiling them on-demand. However, in practice, there are much better ways to do this, such as loading modules via some other Node.js program, or compiling them to JavaScript ahead of time.

Since the Module system is locked, this feature will probably never go away. However, it may have subtle bugs and complexities that are best left untouched.

## __filename#

- {String}

The filename of the code being executed. This is the resolved absolute path of this code file. For a main program this is not necessarily the same filename used in the command line. The value inside a module is the path to that module file.

Example: running `node example.js` from `/Users/mjr`

    console.log(__filename);
    // /Users/mjr/example.js

`__filename` isn't actually a global but rather local to each module.

## __dirname#

- {String}

The name of the directory that the currently executing script resides in.

Example: running `node example.js` from `/Users/mjr`

    console.log(__dirname);
    // /Users/mjr

`__dirname` isn't actually a global but rather local to each module.

## module#

- {Object}

A reference to the current module. In particular `module.exports` is used for defining what a module exports and makes available through `require()`.

`module` isn't actually a global but rather local to each module.

See the module system documentation for more information.

## exports#

A reference to the `module.exports` that is shorter to type. See module system documentation for details on when to use `exports` and when to use `module.exports`.

`exports` isn't actually a global but rather local to each module.

See the module system documentation for more information.

## setTimeout(cb, ms)#

Run callback `cb` after at least `ms` milliseconds. The actual delay depends on external factors like OS timer granularity and system load.

The timeout must be in the range of 1-2,147,483,647 inclusive. If the value is outside that range, it's changed to 1 millisecond. Broadly speaking, a timer cannot span more than 24.8 days.

Returns an opaque value that represents the timer.

## clearTimeout(t)#

Stop a timer that was previously created with `setTimeout()`. The callback will not execute.

## setInterval(cb, ms)#

Run callback `cb` repeatedly every `ms` milliseconds. Note that the actual interval may vary, depending on external factors like OS timer granularity and system load. It's never less than `ms` but it may be longer.

The interval must be in the range of 1-2,147,483,647 inclusive. If the value is outside that range, it's changed to 1 millisecond. Broadly speaking, a timer cannot span more than 24.8 days.

Returns an opaque value that represents the timer.

## clearInterval(t)#

Stop a timer that was previously created with `setInterval()`. The callback will not execute.

The timer functions are global variables. See the timers section.