process.connected属性是流程模块的内置属性，子流程使用该属性来检查其是否与父流程连接。
用法:
process.connected
返回值：如果该进程是从另一个进程派生的，则如果两个进程已连接，则process.connected属性将返回true，否则将返回false。
范例1：如果进程已连接，则process.connected将返回true。
Parent.js
// Require fork method from child_process
// to spawn child process
const fork = require('child_process').fork;
// Child process file
const child_file = 'Child.js';
// Spawn child process
const child = fork(child_file);Child.js
console.log('In Child.js')
// If it is connected
if (process.connected) {
// Print messages
console.log("Child.js is connected");
} else {
// Print messages
console.log("Child.js is disconnected");
}使用以下命令运行Parent.js文件：
node Parent.js
输出：
In Child.js Child.js is connected
范例2：如果该进程已断开连接，则process.connected将返回false。
Parent.js
// Require fork method from child_process
// to spawn child process
const fork = require('child_process').fork;
// Child process file
const child_file = 'Child.js';
// Spawn child process
const child = fork(child_file);Child.js
console.log('In Child.js')
// Disconnect the process
process.disconnect();
// If it is connected
if (process.connected) {
// Print messages
console.log("Child.js is connected");
} else {
// Print messages
console.log("Child.js is disconnected");
}使用以下命令运行Parent.js文件：
node Parent.js
输出：
In Child.js Child.js is disconnected
参考： https://nodejs.org/api/process.html#process_process_connected
注：本文由纯净天空筛选整理自GeeksforGeeks大神的英文原创作品 Node.js process.connected Property。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。