ptdecker

/* Control Flow 3 - Rate Limited Concurrent Execution of an Asynchronous Function
 *
 * Based on:
 *   - http://book.mixu.net/node/ch7.html
 *   - https://github.com/mixu
 *
 * Characteristics:
 *   - Runs a number of operations concurrently
 *   - Starts a limited number of operations concurrently (partial concurrency, full concurrency control)
 *   - No guarantee of order, only that all the operations have been completed

ptdecker

/* Control Flow 2 - Fully Concurrent Executions of a Function (not rate limited)
 *
 * Based on:
 *   - http://book.mixu.net/node/ch7.html
 *   - https://github.com/mixu
 *
 * Characteristics:
 *
 *  - Runs a number of operations concurrently
 *  - Starts all async operations near simultaneously (full concurrency)

ptdecker

/* Control Flow 1 - Repetitive Serial Execution of an Asynchronous Function
 *
 * Based on:
 *   - http://book.mixu.net/node/ch7.html
 *   - https://github.com/mixu
 *
 * Revised to use "typeof(first_item) != 'undefined'" based upon comments from 'Israel'
 *
 * Characteristics:
 *   - Flow control construct 'series' is recursive

ptdecker

/* This addresses a problem with the 'net-watcher.js' example in Jim Wilson's
 * "Node.js The Right Way" book when running his 'net-watcher.js' example under
 * Ubuntu 14.04 (and probably some other *nixs too).
 */

'use strict';

const
    fs = require('fs'),
    net = require('net'),