我想将 cmd 输出写入文件而不是 stdout

Question

我可以使用子进程和 spawn 在 node.js 中执行命令，我希望将此命令的输出写入文件而不是 stdout。

test.js

const expect = require('chai').expect;
const { spawn } = require('child_process')
let path = require('path');
let fs = require('fs');

//tried but didn't work 
1) const cmd = spawn(ansysfnonetclient, options, {
    stdio: [
      0, // Use parent's stdin for child.
      'pipe', // Pipe child's stdout to parent.
      fs.openSync('err.out', 'w') // Direct child's stderr to a file.
    ]
  });

2)  const cmd = spawn(ansysfnonetclient, options,  {shell: true, stdio: 'inherit'});


it('run the cmd and write o/p to file', function (done) {
  this.timeout(30000); 
 let options = ['-h','-o','temp.log'];

 let ansysfnonetclient = path.resolve(__dirname,'../../../../../../../../saoptest/annetclient.exe');

 const cmd = spawn(ansysfnonetclient, options,  {shell: true, stdio: 'inherit'});
 console.log(cmd);
 done();

});

Answer 1

const expect = require('chai').expect;
const { spawn } = require('child_process')
let path = require('path');
let fs = require('fs');

```
const cmd = spawn(ansysfnonetclient, options,  {shell: true, stdio: 'inherit'});

cmd.stdout.on('data',function(chunk) {

fs.writeFile(path.resolve(__dirname,'../../../../../../../../output.log'), chunk.toString(), function(err) {

  if(err) 
  {
    return console.log(err);
  }

  console.log("The file was saved!");
}); 
```

受此启发 post Node.js: Capture STDOUT of `child_process.spawn`

Answer 2

stdio 选项通过 3 "files":

输入
输出
错误输出

如果要将常规输出通过管道传输到文件，则必须将文件作为 stdio 中的第二项传递：

const { spawn } = require('child_process');
const fs = require('fs');

const stdio = [
  0,
  fs.openSync('std.out', 'w'),
  fs.openSync('err.out', 'w')
];

const child = spawn('echo', ['hello world!'], {stdio});

在 https://nodejs.org/api/child_process.html#child_process_options_stdio 阅读更多相关信息。

我想将 cmd 输出写入文件而不是 stdout

I want to write cmd ouput to file instead of stdout

javascript

node.js

testing

npm

child-process