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Questions tagged [child-process]

For questions regarding child-process

In Unix, a child process is typically created as a copy of the parent, using the fork system call. The child process can then overlay itself with a different program (using exec) as required.

Each process may create many child processes but will have at most one parent process; if a process does not have a parent this usually indicates that it was created directly by the kernel.

The inter communication between a child process and a parent process can be done through normal communication schemes such as pipes, sockets, message queues, shared memories.

When a child process terminates, some information is returned to the parent process. When a child process terminates before the parent has called wait, the kernel retains some information about the process, such as its exit status, to enable its parent to call wait later

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node.js run function in child process?

I have a node.js application that receives a file, via a web request and then will apply a conversion process to this file. Since the task is long running this needs to run separate to the main thread. At the moment I have just called the necessary…
Andre M
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node.js: How to spawn detached child in foreground and exit

According to the docs for child_process.spawn I would expect to be able to run a child process in the foreground and allow the node process itself to exit like so: handoff-exec.js: 'use strict'; var spawn = require('child_process').spawn; // this…
coolaj86
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Nodejs child_process spawn get command ran

For clarify purposes I want to see the exact command Node.js runs versus the shell/cli. Unfortunately I can't seem to find out how... https://nodejs.org/api/child_process.html#child_process_child_process_spawn_command_args_options The returned…
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Nodejs child_process spawn custom stdio

I would like to use custom stream to handle child_process.spawn stdio. For example const cp = require('child_process'); const process = require('process'); const stream = require('stream'); var customStream = new…
Mr Br
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Passing node flags/args to child process

If we fork a child_process in Node, how can we pass node parameters to the child_process? https://nodejs.org/api/child_process.html Specifically I would like to spawn ~20 processes, and would like to limit the memory usage of each by using…
Alexander Mills
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Killing a bash script does not kill child processes

I have written a test script which runs another script to start the server to test. When the tests have completed a SIGKILL message is sent to the server process, however when running the test script again the server throws a EADDRINUSE error (I‘m…
Calebmer
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NodeJS child process stdout are all numbers

I'm writing some node.js scripts to kick off a child process. Code snippet is as below. var spawn = require('child_process').spawn; var child = spawn ('node', ['script.js']) child.stdout.on('data', function (data) { …
Lee
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nodejs exec command failing with no useful error message

This is the code to execute cp.exec("cc -Wall /tmp/test.c -o /tmp/test", function(e, stdout, stderr) { if (e) { var errorstr = "Compilation failed with the following error"+ e.message.toString() …
Shrikrishna Holla
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node.js spawned process sticks around if script is killed

Is it possible to make sure that processes spawned with node.js child_process will be killed when the parent is killed? Here's an example script var spawn = require('child_process').spawn; var log_tail = spawn("tail", ["-f",…
case nelson
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Do I have to close inherited handle later owned by child process?

Microsoft played safe here. In their article, "Creating a Child Process with Redirected Input and Output", they are saying: The remaining open handles are cleaned up when this process terminates. To avoid resource leaks in a larger application,…
GSerg
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copy-webpack-plugin configuration issue

Within an electron.js app I'm trying to call and execute a python script from node.js based on the these indicatins: https://nodejs.org/api/child_process.html#child_process_child_process_execfile_file_args_options_callback import { execFile } from…
Raphael10
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how to turn Child_process.spawn's "Promise" syntax to "async/await" syntax

So I have this code and I'm trying to understand the async/await syntax in full depth. The below is the Promise version of the code: function callToolsPromise(req) { return new Promise((resolve, reject) => { let pipshell = 'pipenv'; …
tinnick
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Creating a child process WITHOUT fork()

Is there a way to start a child process without fork(), using execvp() exclusively?
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How can I make child_process.spawn return a Promise in my TypeScript module?

I'm trying to write a little module that uses child_process.spawn to clone a git repo and return a Promise but it fails on me. When I'm using spawnSync it works. Here is the sync code that works. import {spawnSync} from 'child_process'; export…
fabianmoronzirfas
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sanitize user input for child_process.exec command

I'm writing a CLI using node and I've arrived at the part where I take user input and append it to a string that is the command for the child_process.exec function. const CURL_CHILD = exec('npm view --json ' + process.argv[2] + ... I am trying to…
Kraken
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