/// <reference types="node" />
/// <reference types="node" />
/// <reference types="node" />
/// <reference types="node" />
import { SpawnOptionsWithoutStdio, ChildProcess, ChildProcessWithoutNullStreams, Serializable } from 'child_process';
import { Blob } from 'buffer';
import { Stream } from 'stream';
/**
 * Like the unix `which` utility.
 *
 * Finds the first instance of a specified executable in the PATH environment variable.
 *
 * @param String executable
 *
 * @returns String|Null
 */
export declare const where: (executable: string) => string | null;
declare function Sys(): void;
declare namespace Sys {
    var where: (executable: string) => string | null;
    var packager: () => object | Error;
    var installer: (application: string | string[], progress: Function) => Promise<any>;
    var spawning: (command: string, argument: string[], progressOptions: object | SpawningOnProgress, options?: SpawningOptions | undefined) => Promise<string | string[] | null>;
    var isArray: (arg: any) => arg is any[];
    var isUndefined: (value: any) => value is undefined;
    var isBuffer: (value: any) => value is Buffer;
    var isArrayBuffer: (value: any) => value is ArrayBuffer;
    var isString: (value: any) => value is string;
    var isNumber: (value: any) => value is number;
    var isObject: (value: any) => value is object;
    var isObjectOnly: (value: any) => value is object;
    var isBlob: (value: any) => value is Blob;
    var isFunction: (value: any) => value is Function;
    var isDate: (value: any) => value is Date;
    var isStream: (value: any) => value is Stream;
    var isBool: (value: any) => value is boolean;
    var isNull: (value: any) => value is null;
    var isWindows: () => boolean;
    var isLinux: () => boolean;
    var isMac: () => boolean;
}
/**
 * Gets the system package manager install command.
 *
 * @returns {Object}
 *```
 * sudo: boolean, // true or false,
 * command: string, // 'apk-get' - system package manager command,
 * installer: string, // 'sudo apk-get install' - full install command
 *```
 * - Defaults to 'get os-manager installer' if no package manager is found.
 *
 * @throws if `process.platform` is none of darwin, freebsd, linux, sunos or win32.
 */
export declare const packager: () => object | Error;
/**
 * Install package using the system package manager command.
 *
 * @param {String|Array} application package to install.
 * @param {Function} progress callback for any output doing installation.
 * - Any value returned in `callback` will be the final resolved result.
 *
 * @returns {Promise} Promise Output of spawn command.
 * - E.g. 'sudo apg-get install' for Debian based systems.
 * - Defaults to 'get os-manager installer' if no package manager is found.
 * @rejects On any spawn error, or if `process.platform` is none of
 * darwin, freebsd, linux, sunos or win32.
 */
export declare const installer: (application: string | string[], progress: Function) => Promise<any>;
export declare type SpawningOnProgress = (args: {
    spawn: ChildProcessWithoutNullStreams;
    output: any;
    fork: ChildProcess | null;
}) => string | string[] | null;
export declare type SpawningOnError = (err: string) => Error | string;
export declare type SpawningOnMessage = (data: Serializable) => void;
export declare type SpawningOptions = SpawnOptionsWithoutStdio & {
    sudo?: boolean;
    fork?: boolean | null;
    onerror?: null | SpawningOnError;
    onprogress?: null | SpawningOnProgress;
    onmessage?: null | SpawningOnMessage;
};
/**
 * Spawn subprocess with `Promise` features, pass callbacks for `.on('data')` events, with ability to run as admin.
 *
 * @param {String} command - platform command
 * @param {Array} argument - command arguments
 * @param {Function|Object} progressOptions - either callback for `stdout.on('data')` event or `options`.
 * - the callback will receive an object:
 *```js
 * spawn: object, // child process **spawn** `instance`.
 * output: string, // any **output** data.
 * fork: object, // if created, child process **fork** `instance`.
 *```
 * - any `return` is the **`resolve()` .then()** result.
 * @param {Object} options - Any child process `spawn` options, defaults: stdio: 'pipe'.
 * - Additionally:
 *```js
 * sudo: boolean, // run as administrator.
 * fork: string, //  execute an additional module, a child_process.`fork` IPC communication channel.
 * onerror: callable, // callback for `stderr.on('data')` event.
 * onprogress: callable, // callback for `stdout.on('data')` event.
 * onmessage: callable, // callback for `on('message')` for `fork` event.
 *```
 */
export declare const spawning: (command: string, argument: Array<string>, progressOptions: SpawningOnProgress | object, options?: SpawningOptions | undefined) => Promise<string | string[] | null>;
/**
 * Determine if a value is an Array.
 *
 * @param {Object} value The value to test.
 * @returns {boolean} True if value is an Array, otherwise false.
 */
export declare const isArray: (arg: any) => arg is any[];
/**
 * Determine if a value is undefined.
 *
 * @param {Object} value The value to test.
 * @returns {boolean} True if the value is undefined, otherwise false.
 */
export declare const isUndefined: (value: any) => value is undefined;
/**
 * Determine if a value is a Buffer.
 *
 * @param {Object} value The value to test.
 * @returns {boolean} True if value is a Buffer, otherwise false.
 */
export declare const isBuffer: (value: any) => value is Buffer;
/**
 * Determine if a value is an ArrayBuffer.
 *
 * @param {Object} value The value to test.
 * @returns {boolean} True if value is an ArrayBuffer, otherwise false
 */
export declare const isArrayBuffer: (value: any) => value is ArrayBuffer;
/**
 * Determine if a value is a String.
 *
 * @param {Object} value The value to test.
 * @returns {boolean} True if value is a String, otherwise false.
 */
export declare const isString: (value: any) => value is string;
/**
 * Determine if a value is a Number.
 *
 * @param {Object} value The value to test.
 * @returns {boolean} True if value is a Number, otherwise false.
 */
export declare const isNumber: (value: any) => value is number;
/**
 * Determine if a value is an Object
 *
 * @param {Object} value The value to test.
 * @returns {boolean} True if value is an Object, otherwise false.
 */
export declare const isObject: (value: any) => value is object;
/**
 * Determine if a value is only a Object, not an `Array` or `Function`.
 *
 * @param {Object} value The value to test.
 * @return {boolean} True if value is a `Object` only, otherwise false.
 */
export declare const isObjectOnly: (value: any) => value is object;
/**
 * Determine if a value is a Blob
 *
 * @param {Object} value The value to test
 * @returns {boolean} True if value is a Blob, otherwise false
 */
export declare const isBlob: (value: any) => value is Blob;
/**
 * Determine if a value is a Function
 *
 * @param {Object} value The value to test
 * @returns {boolean} True if value is a Function, otherwise false
 */
export declare const isFunction: (value: any) => value is Function;
/**
 * Determine if a value is a Date
 *
 * @param {Object} value The value to test
 * @returns {boolean} True if value is a Date, otherwise false
 */
export declare const isDate: (value: any) => value is Date;
/**
 * Determine if a value is a Stream
 *
 * @param {Object} value The value to test
 * @returns {boolean} True if value is a Stream, otherwise false
 */
export declare const isStream: (value: any) => value is Stream;
/**
 * Determine if a value is a boolean
 *
 * @param {Object} value The value to test
 * @returns {boolean} True if value is a boolean, otherwise false
 */
export declare const isBool: (value: any) => value is boolean;
/**
 * Determine if a value is a null
 *
 * @param {Object} value The value to test
 * @returns {boolean} True if value is a null, otherwise false
 */
export declare const isNull: (value: any) => value is null;
/**
 * Determine if platform is Windows
 *
 * @returns {boolean} True if Windows OS, otherwise false
 */
export declare const isWindows: () => boolean;
/**
 * Determine if platform is Linux
 *
 * @returns {boolean} True if Linux OS, otherwise false
 */
export declare const isLinux: () => boolean;
/**
 * Determine if platform is Apple Mac
 *
 * @returns {boolean} True if Apple macOS, otherwise false
 */
export declare const isMac: () => boolean;
/**
 * Include an `CommonJS` module the old way.
 *
 * @param {string} module
 */
export declare const require: NodeRequire;
export default Sys;
export declare const System: typeof Sys;