Ubuntu: stdout and stderr data is not emitted on child processes (with piped stdio)

[medikoo]

Version

v18.0.0-nightly20220311d8c4e375f2

Platform

Linux parallels-Parallels-Virtual-Platform 5.13.0-37-generic #42~20.04.1-Ubuntu SMP Tue Mar 15 15:44:28 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux

Subsystem

No response

What steps will reproduce the bug?

Run node main.js having following two files in same folder:

child.js

console.log("Some text");

const interval = setInterval(() => {
	console.log("Other text")
}, 100)

setTimeout(() => clearInterval(interval), 1000);

main.js

const childProcess = require('child_process');

const child = childProcess.spawn('node', ['child.js'], { stdio: 'pipe'});

if (child.stdout) {
	console.log("Attach std listeners")
	child.stdout.on('data', data => console.log("Child stdout:", String(data)));
	child.stderr.on('data', data => console.log("Child stderr:", String(data)));
}

child.on('close', (...args) => { console.log("Child closed", args); });

How often does it reproduce? Is there a required condition?

Always

What is the expected behavior?

Expected output (e.g. observable on macOS) is:

Attach std listeners
Child stdout: Some text

Child stdout: Other text

Child stdout: Other text

Child stdout: Other text

Child stdout: Other text

Child stdout: Other text

Child stdout: Other text

Child stdout: Other text

Child stdout: Other text

Child stdout: Other text

Child closed [ 0, null ]

What do you see instead?

Attach std listeners
CLOSED [ 0, null ]

Additional information

When stdio is set to inherit then the child output is exposed as expected.

I observe it on every Node.js version I've tried (v14, v16, v17, and latest build)

[ecalcutin]

I ran some tests on Windows / WSL2 Ubuntu ( just to confirm it works on Node 17.7.1)

uname -a
Linux RADIANT-XPS-17 5.10.60.1-microsoft-standard-WSL2 #1 SMP Wed Aug 25 23:20:18 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux

works as expected
What is a reason you use nightly build ?

[medikoo]

I've just looked more closely, and it appears only to Node.js as installed through snap dependency manager.

This probably should be coined as Ubuntu's Snap bug

[giner]

Temporary workaround #37982 (comment)

[bnoordhuis]

Closing, not a node bug.