doc: recommend events.once to manage 'close' event

doc: recommend events.once to manage 'close' event · nodejs/node@a25d76c

@@ -29,6 +29,7 @@ ls.on('close', (code) => {

29293030```mjs3131import { spawn } from 'node:child_process';32+import { once } from 'node:events';3233const ls = spawn('ls', ['-lh', '/usr']);33343435ls.stdout.on('data', (data) => {

@@ -39,9 +40,8 @@ ls.stderr.on('data', (data) => {

3940console.error(`stderr: ${data}`);4041});414242-ls.on('close', (code) => {43-console.log(`child process exited with code ${code}`);44-});43+const [code] = await once(ls, 'close');44+console.log(`child process exited with code ${code}`);4545```46464747By default, pipes for `stdin`, `stdout`, and `stderr` are established between

@@ -772,6 +772,7 @@ ls.on('close', (code) => {

772772773773```mjs774774import { spawn } from 'node:child_process';775+import { once } from 'node:events';775776const ls = spawn('ls', ['-lh', '/usr']);776777777778ls.stdout.on('data', (data) => {

@@ -782,9 +783,8 @@ ls.stderr.on('data', (data) => {

782783console.error(`stderr: ${data}`);783784});784785785-ls.on('close', (code) => {786-console.log(`child process exited with code ${code}`);787-});786+const [code] = await once(ls, 'close');787+console.log(`child process exited with code ${code}`);788788```789789790790Example: A very elaborate way to run `ps ax | grep ssh`

@@ -1483,6 +1483,7 @@ ls.on('exit', (code) => {

1483148314841484```mjs14851485import { spawn } from 'node:child_process';1486+import { once } from 'node:events';14861487const ls = spawn('ls', ['-lh', '/usr']);1487148814881489ls.stdout.on('data', (data) => {

@@ -1496,6 +1497,9 @@ ls.on('close', (code) => {

14961497ls.on('exit', (code) => {14971498console.log(`child process exited with code ${code}`);14981499});1500+1501+const [code] = await once(ls, 'close');1502+console.log(`child process close all stdio with code ${code}`);14991503```1500150415011505### Event: `'disconnect'`