### Vhost Example

Source: https://github.com/learnboost/cluster/blob/master/History.md

Includes an example demonstrating the usage of virtual hosts (vhosts) within the cluster.

```javascript
// Vhost example code goes here
```

--------------------------------

### Add vhost example

Source: https://github.com/learnboost/cluster/blob/master/History.md

Includes an example demonstrating the usage of virtual hosts (vhosts). This addition helps users understand how to configure and use vhosts within the cluster.

```javascript
/* Added vhost example. Closes #144 */
```

--------------------------------

### Cluster Server Setup with Plugins

Source: https://github.com/learnboost/cluster/blob/master/Readme.md

Configures and starts a Node.js application using the Cluster module, integrating various plugins for logging, statistics, PID files, CLI, and REPL.

```javascript
var cluster = require('cluster')
  , app = require('./app');

cluster(app)
  .use(cluster.logger('logs'))
  .use(cluster.stats())
  .use(cluster.pidfiles('pids'))
  .use(cluster.cli())
  .use(cluster.repl(8888))
  .listen(3000);
```

--------------------------------

### Install Cluster

Source: https://github.com/learnboost/cluster/blob/master/Readme.md

Installs the Cluster module using npm.

```bash
$ npm install cluster
```

--------------------------------

### Cluster Setup by Exporting Server Instance

Source: https://github.com/learnboost/cluster/blob/master/docs/api.md

Illustrates an alternative and recommended method where the server instance is exported from a module and then passed as a path to the cluster function.

```javascript
cluster('app')
  .listen(3000);
```

--------------------------------

### Basic Cluster Setup with HTTP Server

Source: https://github.com/learnboost/cluster/blob/master/docs/api.md

Demonstrates the fundamental usage of the Cluster API by passing an HTTP server instance to the cluster function and then calling listen.

```javascript
var cluster = require('../')
  , http = require('http');

var server = http.createServer(function(req, res){
  res.writeHead(200);
  res.end('Hello World');
});

cluster(server)
  .listen(3000);
```

--------------------------------

### TCP Echo Server Example

Source: https://github.com/learnboost/cluster/blob/master/History.md

Provides an example of a TCP echo server implemented using the cluster module.

```javascript
// TCP echo server example code goes here
```

--------------------------------

### Running Tests

Source: https://github.com/learnboost/cluster/blob/master/Readme.md

Commands to install development dependencies and run tests for the Cluster project.

```bash
$ npm install

$ make test
```

--------------------------------

### Cluster Usage Example

Source: https://github.com/learnboost/cluster/blob/master/docs/debug.md

Demonstrates how to initialize and use the cluster module, including enabling debug output and listening on a specific port.

```javascript
cluster(server)
  .use(cluster.debug())
  .listen(3000);
```

--------------------------------

### Start Telnet Session

Source: https://github.com/learnboost/cluster/blob/master/docs/repl.md

Initiates a telnet session to the REPL socket for interactive administration.

```shell
$ telnet /var/run/cluster.sock
```

--------------------------------

### Cluster Server Setup with CLI

Source: https://github.com/learnboost/cluster/blob/master/docs/cli.md

Demonstrates how to set up a cluster server using the pidfiles and cli plugins. This configuration allows the server script to act as both the master and the CLI interface.

```javascript
var cluster = require('cluster');

cluster(server)
  .use(cluster.pidfiles())
  .use(cluster.cli())
  .listen(3000);
```

--------------------------------

### Cluster Server Setup (Alternative Path)

Source: https://github.com/learnboost/cluster/blob/master/Readme.md

An alternative way to set up the Cluster server, passing the application path directly. This is recommended to prevent unnecessary database connections in the master process.

```javascript
var cluster = require('cluster');

cluster('./app')
  .use(cluster.logger('logs'))
  .use(cluster.stats())
  .use(cluster.pidfiles('pids'))
  .use(cluster.cli())
  .use(cluster.repl(8888))
  .listen(3000);
```

--------------------------------

### Basic HTTP Server Example

Source: https://github.com/learnboost/cluster/blob/master/Readme.md

A simple Node.js HTTP server that logs requests and responds with 'Hello World'. This serves as the application to be managed by Cluster.

```javascript
var http = require('http');

module.exports = http.createServer(function(req, res){
  console.log('%s %s', req.method, req.url);
  var body = 'Hello World';
  res.writeHead(200, { 'Content-Length': body.length });
  res.end(body);
});
```

--------------------------------

### Fix "listening" event by deferring "start"

Source: https://github.com/learnboost/cluster/blob/master/History.md

Corrects the behavior of the "listening" event by deferring the "start" action. This ensures that the event is emitted correctly after the server has fully started.

```javascript
/* Fixed "listening" event by deferring "start" */
```

--------------------------------

### Using Custom Plugins with Cluster

Source: https://github.com/learnboost/cluster/blob/master/docs/api.md

Explains how to integrate custom plugins into the cluster setup by passing a plugin function to the use() method.

```javascript
function myPlugin(path){
  return function(master) {
    // do stuff
  }
}

cluster(server)
  .use(myPlugin('/some/path'))
  .listen(3000);
```

--------------------------------

### Stats Output with Connection and Request Statistics

Source: https://github.com/learnboost/cluster/blob/master/docs/stats.md

Example output from the `stats()` REPL command when both connection and request statistics are enabled, including total requests and per-worker activity.

```text
Workers
connections total: 60
connections active: 0
requests total: 24064
0: 15 seconds 0|4|3358
1: 15 seconds 0|1|1126
2: 15 seconds 0|25|9613
3: 15 seconds 0|30|9967
```

--------------------------------

### Stats Output with Connection Statistics

Source: https://github.com/learnboost/cluster/blob/master/docs/stats.md

Example output from the `stats()` REPL command when connection statistics are enabled, showing total connections, active connections, and per-worker connection details.

```text
Workers
connections total: 60
connections active: 0
0: 15 seconds 0|4
1: 15 seconds 0|1
2: 15 seconds 0|25
3: 15 seconds 0|30
```

--------------------------------

### Abstract Clusters for Job Queues

Source: https://github.com/learnboost/cluster/blob/master/docs/api.md

Shows a minimalist example of using cluster to manage non-server processes, such as job queues, by invoking cluster() without arguments.

```javascript
var cluster = require('cluster');

var proc = cluster().start();

if (proc.isWorker) {
  // do things within the worker processes
} else {
  // do something within the master
}
```

--------------------------------

### Cluster Reload Plugin Usage

Source: https://github.com/learnboost/cluster/blob/master/docs/reload.md

Demonstrates how to use the cluster reload plugin to watch for file changes and restart the server. It shows examples for watching the current directory, a specific directory, multiple paths, and with custom options like signal and file extensions.

```javascript
cluster(server)
  .use(cluster.reload())
  .listen(3000);
```

```javascript
cluster(server)
  .use(cluster.reload('lib'))
  .listen(3000);
```

```javascript
cluster(server)
  .use(cluster.reload(['lib', 'tests', 'index.js']))
  .listen(3000);
```

```javascript
cluster(server)
  .use(cluster.reload('lib', { signal: 'SIGQUIT' }))
  .listen(3000);
```

```javascript
cluster(server)
  .use(cluster.reload('lib', { extensions: ['.js', '.coffee'] }))
  .listen(3000);
```

--------------------------------

### pids() - Get Process IDs

Source: https://github.com/learnboost/cluster/blob/master/docs/repl.md

Outputs the process IDs of the master process and all worker processes.

```APIDOC
pids()
  Outputs the master / worker process ids.
  Example:
    pids
    master: 1799
    worker #0: 1801
    worker #1: 1802
```

--------------------------------

### Checking if Script is a Worker

Source: https://github.com/learnboost/cluster/blob/master/docs/api.md

Provides an example of how to determine if the current script is running as a worker process using the isWorker property.

```javascript
cluster = cluster(server).listen(3000);

if (cluster.isWorker) {
  // do something
}
```

--------------------------------

### Launching the Server and Using CLI Commands

Source: https://github.com/learnboost/cluster/blob/master/docs/cli.md

Shows how to launch the cluster server in the background and then use the CLI commands to interact with the cluster, such as checking status or restarting workers.

```bash
$ nohup node server.js &
$ node server.js status
$ node server.js restart
$ node server.js shutdown
$ node server.js --help
```

--------------------------------

### Basic Cluster Usage with Stats and REPL

Source: https://github.com/learnboost/cluster/blob/master/docs/stats.md

Demonstrates how to initialize a cluster server and enable both the stats and REPL plugins. The REPL is accessible via telnet.

```javascript
cluster(server)
  .use(cluster.stats())
  .use(cluster.repl(8888))
  .listen(3000);
```

--------------------------------

### Launch REPL with Socket

Source: https://github.com/learnboost/cluster/blob/master/docs/repl.md

Launches the REPL with a local Unix domain socket for remote administration.

```javascript
var cluster = require('../');

var server = http.createServer(function(req, res) {
  var body = 'Hello World';
  res.writeHead(200, { 'Content-Length': body.length });
  res.end(body);
});

cluster(server)
  .use(cluster.repl('/var/run/cluster.sock'))
  .listen(3000);
```

--------------------------------

### REPL Commands

Source: https://github.com/learnboost/cluster/blob/master/docs/repl.md

Lists available commands for the Cluster REPL, including help, worker management, and server control.

```APIDOC
REPL Commands:

help(): Display help information
spawn(n): Spawn one or more additional workers. If n is omitted, spawns one worker.
pids(): Output master and worker process IDs.
kill(id, signal): Send signal or SIGTERM to the given worker ID. SIGQUIT can be used for graceful termination.
shutdown(): Gracefully shutdown the server.
stop(): Hard shutdown the server.
restart(): Gracefully restart all workers.
echo(msg): Echo the given message to the REPL client.
stats(): Display server statistics.
```

--------------------------------

### Launch REPL with Port

Source: https://github.com/learnboost/cluster/blob/master/docs/repl.md

Launches the REPL listening on a specified network port, allowing remote connections.

```javascript
var cluster = require('../');
var http = require('http');

var server = http.createServer(function(req, res) {
  var body = 'Hello World';
  res.writeHead(200, { 'Content-Length': body.length });
  res.end(body);
});

cluster(server)
  .use(cluster.repl(8888))
  .listen(3000);
```

--------------------------------

### Expose utils for plugins

Source: https://github.com/learnboost/cluster/blob/master/History.md

Makes utility functions available for use by plugins. This provides plugins with helpful tools for extending the cluster's functionality.

```javascript
/* Added; expose utils, helpful for plugins */
```

--------------------------------

### Configuring Cluster Settings

Source: https://github.com/learnboost/cluster/blob/master/docs/api.md

Shows how to apply various settings to the cluster instance using the set(option, value) method to customize worker count, directories, and timeouts.

```javascript
cluster(server)
  .set('working directory', '/')
  .set('workers', 5)
  .listen(3000);
```

--------------------------------

### Master PreventDefault Support

Source: https://github.com/learnboost/cluster/blob/master/History.md

Introduces `Master#preventDefault` to allow plugins to prevent the master process from its default behavior, such as listening for connections.

```javascript
master.preventDefault();
```

--------------------------------

### Add spawn(-n, signal) support

Source: https://github.com/learnboost/cluster/blob/master/History.md

Adds support for the `spawn()` method with two arguments: a count `-n` and a `signal`. The signal defaults to __SIGQUIT__.

```javascript
/* Added `spawn(-n, signal)` support defaulting to __SIGQUIT__ */
```

--------------------------------

### Pidfiles Helper

Source: https://github.com/learnboost/cluster/blob/master/History.md

Provides a `pidfiles()` helper function for managing process ID files, specifically `master.pidof(name)`.

```javascript
const pid = master.pidof('my_process');
```

--------------------------------

### Enabling Request and Connection Statistics

Source: https://github.com/learnboost/cluster/blob/master/docs/stats.md

Demonstrates enabling both connection and request statistics by passing multiple options to the stats plugin. This provides a comprehensive view of server activity, including total requests.

```javascript
cluster.use(cluster.stats({ connections: true, requests: true }))
```

--------------------------------

### Using Bundled Plugins with Cluster

Source: https://github.com/learnboost/cluster/blob/master/docs/api.md

Demonstrates how to use plugins bundled with the Cluster library, such as the logger plugin, by accessing them from the cluster object.

```javascript
cluster(server)
  .use(cluster.logger())
  .listen(3000);
```

--------------------------------

### Master Spawning Strategy

Source: https://github.com/learnboost/cluster/blob/master/History.md

Implements a master spawning strategy where a new master is spawned to accept connections during restarts, allowing the old master to finish gracefully.

```javascript
// Master spawning strategy implementation
```

--------------------------------

### Add stand-alone restart test

Source: https://github.com/learnboost/cluster/blob/master/History.md

Introduces a test case for the stand-alone restart functionality. This verifies that restarting in standalone mode works correctly.

```javascript
/* Added stand-alone restart test */
```

--------------------------------

### Environment Based Usage with in()

Source: https://github.com/learnboost/cluster/blob/master/History.md

Introduces the `Master#in()` method for environment-specific configurations, allowing different behaviors based on the environment (e.g., 'development', 'production').

```javascript
cluster(server)
  .in('development')
    .use(cluster.debug())
    .use(cluster.repl())
    .listen(3000)
  .in('production')
    .use(cluster.logger())
    .listen(80);
```

--------------------------------

### Fix logger() / pidfiles() errors with mkdirp

Source: https://github.com/learnboost/cluster/blob/master/History.md

Addresses errors in logger() and pidfiles() when the directory does not exist, now utilizing mkdirp. This ensures that necessary directories are created automatically.

```javascript
/* Fixed `logger()` / `pidfiles()` errors when dir does not exist, now using
* mkdirp. Closes #783 */
```

--------------------------------

### Stats REPL Command

Source: https://github.com/learnboost/cluster/blob/master/docs/stats.md

Shows the command to execute within the REPL to display detailed statistics about the master process, system resources, and individual workers.

```javascript
cluster> stats()
```

--------------------------------

### Configure Logger with Default Path and Level

Source: https://github.com/learnboost/cluster/blob/master/docs/logger.md

This snippet demonstrates how to use the logger plugin with its default settings, outputting logs to the default path and using the default log level.

```javascript
cluster(server)
  .use(cluster.logger())
  .listen(3000);
```

--------------------------------

### Add connections option to stats() plugin

Source: https://github.com/learnboost/cluster/blob/master/History.md

Introduces the `connections` option to the `stats()` plugin. This option reports connection and disconnection events, displaying them in the REPL.

```javascript
/* Added `connections` option to `stats()` plugin.
    Reports connections and disconnections, displaying in the REPL. */
```

--------------------------------

### Add spawn(-n) support

Source: https://github.com/learnboost/cluster/blob/master/History.md

Introduces support for the `spawn()` method with a single argument `-n`, specifying the number of workers to spawn.

```javascript
/* Added `spawn(-n)` support. Closes #46 */
```

--------------------------------

### Listen Host DNS Resolution

Source: https://github.com/learnboost/cluster/blob/master/History.md

Enables DNS resolution for the host when using the `listen()` function, allowing for more flexible network configurations.

```javascript
cluster.listen(port, 'hostname.example.com');
```

--------------------------------

### Add simple stand-alone test

Source: https://github.com/learnboost/cluster/blob/master/History.md

Includes a basic test case for the stand-alone mode. This provides a fundamental check for standalone operation.

```javascript
/* Added simple stand-alone test */
```

--------------------------------

### Cluster Filename Support

Source: https://github.com/learnboost/cluster/blob/master/History.md

Adds support for the `cluster(filename)` configuration, which was previously a bug. This feature is highly recommended for advanced usage.

```javascript
cluster(filename);
```

--------------------------------

### spawn() - Spawn Worker

Source: https://github.com/learnboost/cluster/blob/master/docs/repl.md

Spawns a single additional worker process. Use spawn(n) to spawn multiple workers.

```APIDOC
spawn([n])
  Spawn one or more additional workers.
  Parameters:
    n: (Optional) The number of workers to spawn.
  Example:
    spawn()      // Spawns 1 worker
    spawn(4)     // Spawns 4 workers
```

--------------------------------

### Cluster CLI Plugin API Documentation

Source: https://github.com/learnboost/cluster/blob/master/docs/cli.md

Provides API documentation for defining custom commands within the Cluster CLI plugin. It details the `define` method for adding new command-line flags and their associated callback functions.

```APIDOC
cluster.cli.define(flags, callback, description)
  - Defines a new command-line flag and its behavior.
  - Parameters:
    - flags: A string or array of strings representing the command-line flags (e.g., '-h, --help, help').
    - callback: A function that will be executed when the command is invoked. It typically receives the master process object as an argument.
    - description: A string describing the command's purpose, used in the --help output.
  - Example:
    var cli = require('cluster').cli;

    cli.define('-h, --help, help', function(master){
      console.log('\n  Usage: node <file> <command>\n');
      commands.forEach(function(command){
        console.log('    '
      + command.flags.join(', ')
      + '\n    '
      + '\033[90m' + command.desc + '\033[0m'
      + '\n');
      });
      console.log();
      process.exit();
    }, 'Show help information');
  - Related Commands:
    - cluster.cli.define() can be used multiple times to add various commands.
```

--------------------------------

### Enabling Connection Statistics

Source: https://github.com/learnboost/cluster/blob/master/docs/stats.md

Illustrates how to configure the stats plugin to collect connection statistics by passing the `connections: true` option. This enables the display of total and active connections, as well as per-worker connection counts.

```javascript
cluster.use(cluster.stats({ connections: true }))
```

--------------------------------

### Cluster API Reference

Source: https://github.com/learnboost/cluster/blob/master/docs/api.md

Provides a reference for the core Cluster API methods and properties, including listen, set, use, isWorker, isMaster, and state.

```APIDOC
Cluster API:

cluster(server | path | null)
  Initializes the cluster module. Can accept a server instance, a path to a module exporting a server, or null to manage abstract processes.

  .listen(port, [callback])
    Starts the cluster and makes the server listen on the specified port.

  .set(option, value)
    Sets a configuration option for the cluster. Available options include:
      - workers: Number of workers to spawn (defaults to CPU count).
      - working directory: Working directory for workers.
      - backlog: Connection backlog.
      - socket port: Master socket port.
      - timeout: Worker shutdown timeout.
      - title: Master process title.
      - worker title: Worker process title.
      - user: User ID/name for workers.
      - group: Group ID/name for workers.

  .use(plugin)
    Registers a plugin function to extend cluster functionality.

  Master Properties:
    - state: Current state of the master process ('active', 'hard shutdown', 'graceful shutdown').
    - isWorker: Boolean, true if the script is a worker.
    - isMaster: Boolean, true if the script is the master.

  Events:
    - start: IPC server is prepped.
    - worker: A worker is spawned.
    - listening: Server is listening.
    - closing: Master is shutting down.
    - close: Master has shut down.
    - worker killed: A worker has died.
    - worker exception: Worker uncaught exception.
    - kill: Signal being sent to workers.
    - restarting: Restart requested.
    - restart: Restart complete.

  Signals:
    - SIGINT: Hard shutdown.
    - SIGTERM: Hard shutdown.
    - SIGQUIT: Graceful shutdown.
    - SIGUSR2: Restart workers.
```

--------------------------------

### Master do() Method

Source: https://github.com/learnboost/cluster/blob/master/History.md

Adds the `Master#do()` method for executing specific tasks within the master process.

```javascript
master.do('someTask');
```

--------------------------------

### Add support to run cluster without a server

Source: https://github.com/learnboost/cluster/blob/master/History.md

Introduces the capability to run the cluster in a standalone mode without requiring an active server. This expands the flexibility of the cluster.

```javascript
/* Added support to run cluster without a server. Closes #72 */
```

--------------------------------

### Change postpone spawning until "listening"

Source: https://github.com/learnboost/cluster/blob/master/History.md

Defers the spawning of new processes until the "listening" event occurs. This change aims to resolve an EINVAL issue by ensuring proper initialization before spawning.

```javascript
/* Changed; postpone spawning until "listening" this _should_ fix our EINVAL issue */
```

--------------------------------

### Add title and worker title settings

Source: https://github.com/learnboost/cluster/blob/master/History.md

Introduces `title` and `worker title` settings. These settings allow customization of the process titles for the master and worker processes.

```javascript
/* Added `title` and `worker title` settings. Closes #54 */
```

--------------------------------

### REPL Shutdown and Stop Functions

Source: https://github.com/learnboost/cluster/blob/master/History.md

Adds `shutdown()` and `stop()` functions to the REPL (Read-Eval-Print Loop) for controlling the cluster process.

```javascript
repl.shutdown();
repl.stop();
```

--------------------------------

### Fix Master#listen() with env specific config

Source: https://github.com/learnboost/cluster/blob/master/History.md

Corrects the behavior of Master#listen() when using environment-specific configurations. This ensures that listening is configured correctly based on the environment.

```javascript
/* Fixed `Master#listen()` with env specific config. Closes #98 */
```

--------------------------------

### Configure Logger with Custom Path

Source: https://github.com/learnboost/cluster/blob/master/docs/logger.md

This snippet shows how to specify a custom directory for log files using the logger plugin. Logs will be written to the specified path.

```javascript
cluster(server)
  .use(cluster.logger('tmp/logs'))
  .listen(3000);
```

--------------------------------

### Fix stand-alone support with file path

Source: https://github.com/learnboost/cluster/blob/master/History.md

Corrects the stand-alone support when a file path is provided. This ensures that the cluster can be run correctly in standalone mode with file path configurations.

```javascript
/* Fixed stand-alone support with a file path. Closes #141 [reported by SebastianEdwards] */
```

--------------------------------

### restart() - Restart Workers

Source: https://github.com/learnboost/cluster/blob/master/docs/repl.md

Gracefully restarts all worker processes.

```APIDOC
restart()
  Gracefully restart all workers.
```

--------------------------------

### Fix user / group options

Source: https://github.com/learnboost/cluster/blob/master/History.md

Corrects issues with the `user` and `group` configuration options. This ensures that user and group settings are applied correctly.

```javascript
/* Fixed `user` / `group` options. Closes #60 */
```

--------------------------------

### Cluster Debug Output

Source: https://github.com/learnboost/cluster/blob/master/docs/debug.md

This section shows the typical verbose debugging information output to stderr during the lifecycle of a cluster, including startup, worker connections, and shutdown events.

```log
info - master started
info - worker 0 spawned
info - worker 1 spawned
info - worker 2 spawned
info - worker 3 spawned
info - worker 2 connected
info - worker 0 connected
info - worker 3 connected
info - worker 1 connected
info - listening for connections
^C  info - shutting down
  warning - kill(SIGKILL)
  info - shutdown complete
  warning - worker 2 died
  warning - worker 0 died
  warning - worker 3 died
```

--------------------------------

### Fix repl() bug

Source: https://github.com/learnboost/cluster/blob/master/History.md

Ensures the server exists before closing it in the repl() function. This addresses a specific bug related to server existence checks.

```javascript
/* Fixed `repl()` bug: ensure server exists before closing it */
```

--------------------------------

### Add support for plugins to work within workers

Source: https://github.com/learnboost/cluster/blob/master/History.md

Enables plugins to function correctly within worker processes. This expands the capabilities of plugins by allowing them to operate in different process contexts.

```javascript
/* Added support for plugins to work within workers. Closes #27 */
```

--------------------------------

### Log Dependency in package.json

Source: https://github.com/learnboost/cluster/blob/master/History.md

Specifies the 'log' module as a dependency in the `package.json` file.

```json
{
  "dependencies": {
    "log": "*"
  }
}
```

--------------------------------

### Default Master#spawn() and Master#remove() to 1

Source: https://github.com/learnboost/cluster/blob/master/History.md

Sets the default value for `Master#spawn()` and `Master#remove()` to 1. This simplifies their usage by providing a default count.

```javascript
/* Added; default both `Master#spawn()` and `Master#remove()` to 1 */
```

--------------------------------

### Add support for changing watched file extensions

Source: https://github.com/learnboost/cluster/blob/master/History.md

Enables support for dynamically changing the file extensions that the cluster watches for reloads. This provides flexibility in configuring watched files.

```javascript
/* Added support for changing watched file extensions [Eiríkur Nilsson] */
```

--------------------------------

### Remove 0.2.x compatibility

Source: https://github.com/learnboost/cluster/blob/master/History.md

Discontinues compatibility with Node.js 0.2.x. This simplifies the codebase and focuses on newer Node.js versions.

```javascript
/* Removed 0.2.x compatibility */
```

--------------------------------

### Fix cli() plugin

Source: https://github.com/learnboost/cluster/blob/master/History.md

Addresses an issue with the cli() plugin, resolving a reported problem. This fix enhances the functionality and stability of the CLI plugin.

```javascript
/* Fixed `cli()` plugin. Closes #145 [reported by alefnula] */
```

--------------------------------

### Save PID Files

Source: https://github.com/learnboost/cluster/blob/master/docs/pidfiles.md

Saves PID files to a specified directory. If no path is provided, it defaults to './pids'. This plugin is used within the cluster configuration.

```javascript
cluster(server)
  .use(cluster.pidfiles())
  .listen(3000);
```

```javascript
cluster(server)
  .use(cluster.pidfiles('/var/run/node'))
  .listen(3000);
```

--------------------------------

### Restarts Statistics

Source: https://github.com/learnboost/cluster/blob/master/History.md

Adds functionality to track and display statistics related to process restarts.

```javascript
cluster.getRestartStats();
```

--------------------------------

### Expose child Worker instance .worker

Source: https://github.com/learnboost/cluster/blob/master/History.md

Makes the child Worker instance accessible via the .worker property. This allows for direct interaction with worker instances.

```javascript
/* Expose child `Worker` instance `.worker` */
```

--------------------------------

### Add support for calling master method from worker

Source: https://github.com/learnboost/cluster/blob/master/History.md

Enables the ability to call any master method directly from a worker process. This enhances inter-process communication and control.

```javascript
/* Added support for calling any master method from a worker [felixge] */
```

--------------------------------

### Remove remaining 2.x support

Source: https://github.com/learnboost/cluster/blob/master/History.md

Eliminates all remaining support for Node.js 2.x. This change focuses the project on newer Node.js versions.

```javascript
/* Removed remaining 2.x support. Closes #108 */
```

--------------------------------

### Cluster PID File Management

Source: https://github.com/learnboost/cluster/blob/master/docs/pidfiles.md

Provides API methods for managing PID files within the cluster. Includes accessing the PID directory and retrieving PIDs by name.

```APIDOC
master.pidfiles
  Description: The directory where PID files are saved.

master.pidof(name)
  Description: Returns the process ID (PID) for a given name.
  Parameters:
    name: The name of the process (e.g., 'master', 'worker.0').
  Returns: The PID as a number.
  Example:
    master.pidof('master')
    // => 5978

    master.pidof('worker.0')
    // => 5979
```

--------------------------------

### Maintaining Worker Count on SIGCHLD

Source: https://github.com/learnboost/cluster/blob/master/History.md

Ensures the worker count is maintained correctly upon receiving the `__SIGCHLD__` signal.

```javascript
process.on('SIGCHLD', () => {
  // Maintain worker count
});
```

--------------------------------

### kill(id, [signal]) - Kill Worker

Source: https://github.com/learnboost/cluster/blob/master/docs/repl.md

Sends a signal to a specific worker process. Defaults to SIGTERM if no signal is provided.

```APIDOC
kill(id[, signal])
  Kill worker `id` with the given `signal` or __SIGTERM__.
  Parameters:
    id: The ID of the worker to kill.
    signal: (Optional) The signal to send (e.g., 'SIGTERM', 'SIGQUIT'). Defaults to 'SIGTERM'.
  Example:
    kill(2)
    kill(3, 'SIGQUIT')
```

--------------------------------

### Worker Management and Shutdown

Source: https://github.com/learnboost/cluster/blob/master/docs/api.md

API methods for managing worker processes, including spawning, graceful shutdown, hard shutdown, and restarting.

```APIDOC
Master#spawn(n)
  Spawn `n` additional workers.

Master#close()
  Graceful shutdown, waits for all workers to reply before exiting.

Master#destroy()
  Hard shutdown, immediately kill all workers.

Master#restart([signal])
  Defaults to a graceful restart, spawning a new master process, and sending __SIGQUIT__ to the previous master process. Alternatively a custom `signal` may be passed.

Master#kill([signal])
  Sends __SIGTERM__ or `signal` to all worker processes. This method is used by `Master#restart()`, `Master#close()` etc.
```

--------------------------------

### Add requests option to stats() plugin

Source: https://github.com/learnboost/cluster/blob/master/History.md

Adds the `requests` option to the `stats()` plugin. This option reports request statistics, displaying them in the REPL.

```javascript
/* Added `requests` option to `stats()` plugin.
    Reports request statistics, displaying in the REPL. */
```

--------------------------------

### Add cyclic restart timeouts

Source: https://github.com/learnboost/cluster/blob/master/History.md

Introduces timeouts for cyclic restarts. This prevents infinite restart loops by setting a limit on restart attempts.

```javascript
/* Added cyclic restart timeouts. Closes #23 */
```

--------------------------------

### Add test case for #125

Source: https://github.com/learnboost/cluster/blob/master/History.md

Includes a new test case to specifically address issue #125. This enhances test coverage and ensures the fix for #125 is effective.

```javascript
/* Added test case for #125 [felixge] */
```

--------------------------------

### Configure Logger with Custom Path and Debug Level

Source: https://github.com/learnboost/cluster/blob/master/docs/logger.md

This snippet illustrates configuring the logger plugin with both a custom log directory and a specific log level ('debug') for increased verbosity.

```javascript
cluster(server)
  .use(cluster.logger('/var/log/node', 'debug'))
  .listen(3000);
```

--------------------------------

### Graceful Shutdown with -g Flag

Source: https://github.com/learnboost/cluster/blob/master/History.md

Replaces the duplicate `-s` flag with `-g` for graceful shutdown, improving process management.

```bash
node app.js -g
```

--------------------------------

### Fix reload() using extname() instead of indexOf()

Source: https://github.com/learnboost/cluster/blob/master/History.md

Corrects the `reload()` function to use `extname()` instead of `indexOf()` for determining file extensions. This ensures more accurate file extension handling.

```javascript
/* Fixed; reload() using extname() instead of indexOf() [reported by solsys] */
```

--------------------------------

### Define REPL Function

Source: https://github.com/learnboost/cluster/blob/master/docs/repl.md

Defines a custom function accessible within the REPL. The function receives the master instance, the REPL socket, and any arguments passed.

```javascript
var cluster = require('../');
var repl = cluster.repl;

repl.define('echo', function(master, sock, msg) {
  sock.write(msg + '\n');
}, 'echo the given message');

// Example usage in REPL:
// echo('Hello from REPL!');
```

--------------------------------

### Stats Plugin Event: Client Connection

Source: https://github.com/learnboost/cluster/blob/master/docs/stats.md

Details the event emitted when a client connects to the server, including the associated worker.

```text
client connection, worker
```

--------------------------------

### Add stand-alone shutdown test

Source: https://github.com/learnboost/cluster/blob/master/History.md

Adds a test case for the stand-alone shutdown functionality. This ensures that the cluster can be shut down properly in standalone mode.

```javascript
/* Added stand-alone shutdown test */
```

--------------------------------

### Fix abort on many immediate worker deaths

Source: https://github.com/learnboost/cluster/blob/master/History.md

Ensures that the process aborts gracefully when multiple workers die immediately during boot. This prevents cascading failures.

```javascript
/* Fixed; abort on many immediate worker deaths within boot */
```

--------------------------------

### Change exit > 0 when using cli() when cluster not running

Source: https://github.com/learnboost/cluster/blob/master/History.md

Modifies the behavior to exit with a status code greater than 0 when attempting to use the `cli()` function while the cluster is not running. This provides clearer feedback on the cluster's state.

```javascript
/* Changed; exit > 0 when trying to use the `cli()` when cluster is not running */
```

--------------------------------

### Remove unnecessary use of client socket

Source: https://github.com/learnboost/cluster/blob/master/History.md

Eliminates the unnecessary use of client sockets, which was causing bind() errors. This optimization improves socket handling and prevents binding issues.

```javascript
/* Removed unnecessary use of client socket causing `bind()` errors */
```

--------------------------------

### Process.setuid() Typo Fix

Source: https://github.com/learnboost/cluster/blob/master/History.md

Corrects a typo in the `process.setuid()` function call.

```javascript
process.setuid('user'); // Corrected
```

--------------------------------

### Add request complete stats() event

Source: https://github.com/learnboost/cluster/blob/master/History.md

Introduces a "request complete" event to the `stats()` function. This event is emitted when a request finishes, providing lifecycle information.

```javascript
/* Added `request complete` `stats()` event */
```

--------------------------------

### Change internal IPC to use UDP

Source: https://github.com/learnboost/cluster/blob/master/History.md

Switches the internal Inter-Process Communication (IPC) mechanism to use UDP. This change aims to improve the efficiency and reliability of communication between processes.

```javascript
/* Changed internal IPC to use UDP. Closes #126 */
```

--------------------------------

### Change cli() to operate on orphans

Source: https://github.com/learnboost/cluster/blob/master/History.md

Updates the `cli()` function to continue operating on orphaned child processes. This ensures that CLI commands can still manage processes even if they become orphaned.

```javascript
/* Changed; `cli()` will still operate on orphans */
```

--------------------------------

### Fix .listen() return value

Source: https://github.com/learnboost/cluster/blob/master/History.md

Corrects the return value of the .listen() method. This change ensures that the method behaves as expected and returns the correct value upon successful listening.

```javascript
/* Fixed `.listen()` return value. Closes #149 [nibblebot] */
```

--------------------------------

### Stats Plugin Event: Client Request

Source: https://github.com/learnboost/cluster/blob/master/docs/stats.md

Details the event emitted when a client makes a request, including the associated worker and request details.

```text
client request, worker, request
```

--------------------------------

### Change demote user/group in master

Source: https://github.com/learnboost/cluster/blob/master/History.md

Modifies the master process to demote its user and group privileges. This is a security enhancement to run with fewer privileges.

```javascript
/* Changed; demote user/group in master */
```

--------------------------------

### Revert "Changed; demote user/group in master"

Source: https://github.com/learnboost/cluster/blob/master/History.md

Reverts a previous change that demoted the user/group in the master process. This restores the previous behavior regarding user/group privileges.

```javascript
/* Revert "Changed; demote user/group in master" */
```

--------------------------------

### Cluster Worker ID Environment Variable

Source: https://github.com/learnboost/cluster/blob/master/History.md

Introduces the `__CLUSTER_WORKER__` environment variable to identify worker IDs within the cluster.

```javascript
process.env.__CLUSTER_WORKER__ = workerId;
```

--------------------------------

### Fix __SIGKILL__ children on master uncaught exception

Source: https://github.com/learnboost/cluster/blob/master/History.md

Ensures that child processes are killed with __SIGKILL__ when an uncaught exception occurs in the master process. This provides a more robust shutdown mechanism.

```javascript
/* Fixed: __SIGKILL__ children on master uncaught exception */
```

--------------------------------

### Worker Exception Event

Source: https://github.com/learnboost/cluster/blob/master/History.md

Introduces a new 'worker exception' event to handle exceptions occurring within worker processes.

```javascript
master.on('worker exception', (worker, error) => {
  // Handle worker exception
});
```

--------------------------------

### Fix typo in reload() plugin

Source: https://github.com/learnboost/cluster/blob/master/History.md

Corrects a typo in the reload() plugin that caused the 'signal' option to fail. This fix ensures that the signal option functions correctly.

```javascript
/* Fixed typo in `reload()` plugin causing the `signal` option to fail. Closes #131 */
```

--------------------------------

### Fix cli() hang regression

Source: https://github.com/learnboost/cluster/blob/master/History.md

Resolves a regression that caused the cli() function to hang. This fix improves the stability and responsiveness of the command-line interface.

```javascript
/* Fixed `cli()` hang regression. Closes #148 */
```

--------------------------------

### Conditional Execution with `in()`

Source: https://github.com/learnboost/cluster/blob/master/docs/api.md

Conditionally perform actions based on the NODE_ENV. The `in()` method allows chaining multiple environment-specific configurations.

```javascript
cluster(server)
  .in('development').use(cluster.debug())
  .in('development').listen(3000)
  .in('production').listen(80);
```

```javascript
cluster(server)
  .set('working directory', '/')
  .in('development')
    .set('workers', 1)
    .use(cluster.logger('logs', 'debug'))
    .use(cluster.debug())
    .listen(3000)
  .in('production')
    .set('workers', 4)
    .use(cluster.logger())
    .use(cluster.pidfiles())
    .listen(80);
```

```javascript
cluster(server)
  .set('working directory', '/')
  .do(function(){
    console.log('some arbitrary action');
  })
  .in('development')
    .set('workers', 1)
    .use(cluster.logger('logs', 'debug'))
    .use(cluster.debug())
  .in('production')
    .set('workers', 4)
    .use(cluster.logger())
    .use(cluster.pidfiles())
  .in('all')
    .listen(80);
```

--------------------------------

### Change cli commands to signal orphaned children

Source: https://github.com/learnboost/cluster/blob/master/History.md

Modifies CLI commands to signal orphaned child processes. This improves the management of child processes, ensuring they are properly handled.

```javascript
/* Changed; cli commands will now signal orphaned children */
```

--------------------------------

### Fix standalone read from stdin regression

Source: https://github.com/learnboost/cluster/blob/master/History.md

Addresses a regression in standalone read from stdin, specifically related to the __ENOTSOCK__ error. This fix aims to resolve issues where the server socket is not properly handled.

```javascript
/* Fixed standalone read from stdin (__ENOTSOCK__) regression. Closes #153 */
```

--------------------------------

### Add lightRequests option to stats()

Source: https://github.com/learnboost/cluster/blob/master/History.md

Introduces the `lightRequests` option to the `stats()` function. This option likely controls the verbosity or type of request statistics reported.

```javascript
/* Added `lightRequests` option to `stats()` */
```

--------------------------------

### SIGCHLD Trap for Worker Notification

Source: https://github.com/learnboost/cluster/blob/master/History.md

Implements a `__SIGCHLD__` trap to notify the master process when a worker is killed, enabling recovery.

```javascript
process.on('SIGCHLD', () => {
  // Notify master of killed worker
});
```

--------------------------------

### Change use preventDefault instead of exit() in cli()

Source: https://github.com/learnboost/cluster/blob/master/History.md

Replaces the use of exit() with preventDefault() within the cli() function. This change likely affects how events are handled in the CLI, preventing premature exits.

```javascript
/* Changed: use preventDefault instead of `exit()` in `cli()` */
```

--------------------------------

### Fix cli() exit when working with reload()

Source: https://github.com/learnboost/cluster/blob/master/History.md

Resolves an issue where `cli()` would exit unexpectedly when used in conjunction with `reload()` or other functions that keep the event loop active. This ensures proper CLI behavior in such scenarios.

```javascript
/* Fixed `cli()` exit when working with `reload()` (or anything else keeping the event loop active) */
```

--------------------------------

### Fix stand-alone issue with not killing parent master

Source: https://github.com/learnboost/cluster/blob/master/History.md

Resolves an issue in standalone mode where the parent master process was not being killed. This ensures proper process management during shutdown.

```javascript
/* Fixed stand-alone issue with not killing the parent master. Closes #565 */
```

--------------------------------

### Fix close(fd) issue for Master without server

Source: https://github.com/learnboost/cluster/blob/master/History.md

Addresses a `close(fd)` issue encountered by the Master process when it does not have an associated server. This prevents errors related to file descriptor handling.

```javascript
/* Fixed `close(fd)` issue for Master without a server. Closes #89 */
```

--------------------------------

### Add { color: false } option to debug()

Source: https://github.com/learnboost/cluster/blob/master/History.md

Introduces an option `{ color: false }` for the `debug()` function. This allows disabling color output for debugging messages.

```javascript
/* Added `{ color: false }` option to `debug()` */
```

--------------------------------

### Reload() Filtering

Source: https://github.com/learnboost/cluster/blob/master/History.md

Modifies the `reload()` function to filter out non-JavaScript files and defaults to the server's root directory.

```javascript
cluster.reload(); // Defaults to server root and filters non-js files
```

--------------------------------

### Fix IPC for workers without a server

Source: https://github.com/learnboost/cluster/blob/master/History.md

Resolves an Inter-Process Communication (IPC) issue that occurred for workers not associated with a server. This ensures proper communication even in serverless worker scenarios.

```javascript
/* Fixed IPC for workers without a server. Closes #91 */
```

--------------------------------

### Fix err.code check

Source: https://github.com/learnboost/cluster/blob/master/History.md

Corrects an issue with checking the err.code property. This ensures that error handling logic is robust and correctly identifies error conditions.

```javascript
/* Fixed an `err.code` check */
```

--------------------------------

### Change sync unlink of server / client sockets

Source: https://github.com/learnboost/cluster/blob/master/History.md

Modifies the unlinking of server and client sockets to be synchronous. This ensures that sockets are properly cleaned up before proceeding.

```javascript
/* Changed: sync unlink of server / client sockets */
```

--------------------------------

### Fix clobbering of "worker exception"

Source: https://github.com/learnboost/cluster/blob/master/History.md

Resolves an issue where "worker exception" messages were being clobbered. This fix ensures that worker exception information is preserved and reported correctly.

```javascript
/* Fixed clobbering of "worker exception" [reported by fredericosilva] */
```

--------------------------------

### Fix json framing

Source: https://github.com/learnboost/cluster/blob/master/History.md

Corrects an issue related to JSON framing. This ensures that JSON data is transmitted and received correctly between processes.

```javascript
/* Fix for json framing. Closes #109 */
```

--------------------------------

### Change nextTick() uncaughtException handler

Source: https://github.com/learnboost/cluster/blob/master/History.md

Modifies the uncaughtException handler for nextTick(). This change likely improves error handling and prevents unexpected application termination.

```javascript
/* Changed: nextTick() uncaughtException handler */
```

--------------------------------

### Remove master __SIGHUP__ as restart

Source: https://github.com/learnboost/cluster/blob/master/History.md

Removes the handling of __SIGHUP__ signal for restarting the master process. This change likely alters the restart mechanism.

```javascript
/* Remove master __SIGHUP__ as restart */
```

--------------------------------

### Checking if Script is the Master

Source: https://github.com/learnboost/cluster/blob/master/docs/api.md

Illustrates how to check if the current script is the master process using the isMaster property.

```javascript
cluster = cluster(server).listen(3000);

if (cluster.isMaster) {
  // do something
}
```

--------------------------------

### Rename titles to "cluster" and "cluster worker"

Source: https://github.com/learnboost/cluster/blob/master/History.md

Renames internal titles to "cluster" and "cluster worker" for clarity. This change improves the internal naming conventions.

```javascript
/* Renamed titles to "cluster" and "cluster worker". closes #82 */
```

--------------------------------

### Remove local socket usage

Source: https://github.com/learnboost/cluster/blob/master/History.md

Removes the usage of local sockets as they are being phased out from Node.js. This change aligns the project with Node.js core developments.

```javascript
/* Removed local socket usage as it is being removed from node */
```

--------------------------------

### Fix restart race-condition

Source: https://github.com/learnboost/cluster/blob/master/History.md

Resolves a race condition that could occur during restarts. This improves the reliability of the restart process.

```javascript
/* Fixed restart race-condition. Closes #125 */
```

--------------------------------

### Stats Plugin Event: Client Disconnection

Source: https://github.com/learnboost/cluster/blob/master/docs/stats.md

Details the event emitted when a client disconnects from the server, including the associated worker.

```text
client disconnection, worker
```

--------------------------------

### Change only caught uncaughtExceptions when no other listeners

Source: https://github.com/learnboost/cluster/blob/master/History.md

Modifies the behavior to only catch uncaught exceptions when there are no other listeners attached. This prevents interference with other error handling mechanisms.

```javascript
/* Changed; only caught uncaughtExceptions when no other listeners are present */
```

--------------------------------

### Fix close socketpair fds when worker dies

Source: https://github.com/learnboost/cluster/blob/master/History.md

Ensures that socketpair file descriptors (fds) are properly closed when a worker process dies. This prevents resource leaks.

```javascript
/* Fixed; close socketpair fds when worker dies */
```

--------------------------------

### Change reload() to reload workers only

Source: https://github.com/learnboost/cluster/blob/master/History.md

Updates the reload() functionality to exclusively reload workers. This change refines the reload process, focusing only on worker processes.

```javascript
/* Changed `reload()` to reload workers only */
```

--------------------------------

### Fix json framing race-condition

Source: https://github.com/learnboost/cluster/blob/master/History.md

Resolves a race condition related to JSON framing. This ensures that JSON data is handled reliably during concurrent operations.

```javascript
/* Fixed json framing race-condition. Closes #64 */
```