Send the same bash process multiple commands

Question

I have the following code:

const cp = require('child_process');

function spawnInstance () {
  const c = cp.spawn('bash');
  return command => {
    return new Promise((resolve, reject) => {
      c.stdout.on('data', d => resolve(String(d || 'empty stdout.\n')));
      c.stderr.once('data', d => reject(String(d || 'empty stderr.\n')));
      c.stdin.write(`echo "${command}" | bash;`);  
      c.stdin.write('\n');
    });
  };
}

(async () => {
  const bash = spawnInstance();
  console.log(await bash('ls'));
  console.log(await bash('cd node_modules'));
  console.log(await bash('ls'));
})()
.catch(e =>
  console.error(e)
);

What I want to do is to reuse the same bash process, and get the stdout for each command that I run. Is there a way to do this, or do I need to start a new bash process for each command I run?

The problem is my code gets stuck on the cd node_modules command.

jmd_dk · Accepted Answer · 2018-03-26 21:56:39Z

1

I don't think you can keep a bash process alive after a bash call and then re-enter the process with some new call. You can however run multiple bash commands after each other in the same process, e.g. by separating them with semicolons:

console.log(await bash('cd node_modules; ls'));

answered Mar 26, 2018 at 21:56

jmd_dk

13.2k11 gold badges71 silver badges104 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

scrat.squirrel · Accepted Answer · 2021-03-17 02:06:24Z

1

This article states that now there is an NPM package that allows for a persistent bash process.

The github url:

https://github.com/bitsofinfo/stateful-process-command-proxy

Quote from the him homepage:

This node module can be used for proxying long-lived bash process, windows console etc. It works and has been tested on both linux, os-x and windows hosts running the latest version of node.

answered Mar 17, 2021 at 2:06

scrat.squirrel

3,89430 silver badges35 bronze badges

Collectives™ on Stack Overflow

Send the same bash process multiple commands

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related