[nodemon] app crashed - waiting for file changes before starting...解决方法

安装时出现的问题及解决方法：

[nodemon] starting `node app.js`
events.js:291
      throw er; // Unhandled 'error' event
      ^

Error: listen EADDRINUSE: address already in use :::3000
    at Server.setupListenHandle [as _listen2] (net.js:1316:16)
    at listenInCluster (net.js:1364:12)
    at Server.listen (net.js:1450:7)
    at Application.listen (/Users/edz/Documents/ketang/firstServer/node_modules/koa/lib/application.js:82:19)
    at Object.<anonymous> (/Users/edz/Documents/ketang/firstServer/app.js:70:22)
    at Module._compile (internal/modules/cjs/loader.js:1256:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1277:10)
    at Module.load (internal/modules/cjs/loader.js:1105:32)
    at Function.Module._load (internal/modules/cjs/loader.js:967:14)
    at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:60:12)
    at internal/main/run_main_module.js:17:47
Emitted 'error' event on Server instance at:
    at emitErrorNT (net.js:1343:8)
    at processTicksAndRejections (internal/process/task_queues.js:80:21) {
  code: 'EADDRINUSE',
  errno: -48,
  syscall: 'listen',
  address: '::',
  port: 3000
}
[nodemon] app crashed - waiting for file changes before starting...

error：[nodemon] app crashed - waiting for file changes before starting...

解决方法：

1. 输入：firstServer edz$ lsof -i tcp:3000

^CedzdeMacBook-Air:firstServer edz$ lsof -i tcp:3000
COMMAND     PID USER   FD   TYPE             DEVICE SIZE/OFF NODE NAME
Google      373  edz   20u  IPv6 0x24a988475a8be9bb      0t0  TCP localhost:61623->localhost:hbci (CLOSE_WAIT)
Google      373  edz   28u  IPv6 0x24a988475a8bfafb      0t0  TCP localhost:61624->localhost:hbci (CLOSE_WAIT)
node      23731  edz   24u  IPv6 0x24a988475a8c067b      0t0  TCP *:hbci (LISTEN)


输入：
firstServer edz$ kill 23731  //删除最后一个 23731

2. 删除后再次输入：firstServer edz$ lsof -i tcp:3000，检验是否删除成功

edzdeMacBook-Air:firstServer edz$ lsof -i tcp:3000

得到：
COMMAND   PID USER   FD   TYPE             DEVICE SIZE/OFF NODE NAME
Google    373  edz   20u  IPv6 0x24a988475a8be9bb      0t0  TCP localhost:61623->localhost:hbci (CLOSE_WAIT)
Google    373  edz   28u  IPv6 0x24a988475a8bfafb      0t0  TCP localhost:61624->localhost:hbci (CLOSE_WAIT)
//检查是否成功

3. 再次运行

edzdeMacBook-Air:firstServer edz$ nodemon app.js
[nodemon] 2.0.4
[nodemon] to restart at any time, enter `rs`
[nodemon] watching path(s): *.*
[nodemon] watching extensions: js,mjs,json
[nodemon] starting `node app.js`
Listening on http://localhost:3000

//出现以上内容，成功