Node.js spawn 非同期実行 シェルスクリプトを実行するサンプル
環境
Windows 10 Home 64bit
node v16.17.0
npm 8.15.0
構文
const { spawn } = require('child_process’)
大きいデータを扱う場合、ストリーム形式である spawnを利用します。
使用例
const { spawn } = require('child_process')
const childProcess = spawn('cat', ['test.txt'])
console.log('process id:' + process.pid)
console.log('child process id:' + childProcess.pid)
childProcess.stdout.on('data', (chunk) => {
console.log(new Date())
console.log(chunk.length)
})
const { spawn } = require('child_process')
const childProcess = spawn('cat', ['test.txt'])
console.log('process id:' + process.pid)
console.log('child process id:' + childProcess.pid)
childProcess.stdout.on('data', (chunk) => {
console.log(new Date())
console.log(chunk.length)
})
const { spawn } = require('child_process')
const childProcess = spawn('cat', ['test.txt'])
console.log('process id:' + process.pid)
console.log('child process id:' + childProcess.pid)
childProcess.stdout.on('data', (chunk) => {
console.log(new Date())
console.log(chunk.length)
})
実行結果
$ node spawn.js
process id:44066
child process id:44093
2023-11-21T17:20:48.073Z
8192
2023-11-21T17:20:48.076Z
8192
2023-11-21T17:20:48.076Z
4782
$ node spawn.js
process id:44066
child process id:44093
2023-11-21T17:20:48.073Z
8192
2023-11-21T17:20:48.076Z
8192
2023-11-21T17:20:48.076Z
4782
$ node spawn.js process id:44066 child process id:44093 2023-11-21T17:20:48.073Z 8192 2023-11-21T17:20:48.076Z 8192 2023-11-21T17:20:48.076Z 4782