search
HomeBackend DevelopmentGolangHow to Execute a Command in Go and Detach It from the Parent Process?

How to Execute a Command in Go and Detach It from the Parent Process?

Run Command in Go and Detach It from Process

In Go, you can execute a command in a detached manner, allowing it to run independently of your program. Here's how you can achieve this:

Code:

<code class="go">package main

import (
    "fmt"
    "log"
    "os"
    "os/exec"
    "strconv"
    "syscall"
)

func main() {
    // Define the command and its arguments
    cmd := exec.Command("sleep", "120")

    // Set up the pipes for stdout and stderr
    stdoutPipe, err := cmd.StdoutPipe()
    if err != nil {
        log.Fatal(err)
    }
    stderrPipe, err := cmd.StderrPipe()
    if err != nil {
        log.Fatal(err)
    }

    // Start the command
    if err := cmd.Start(); err != nil {
        log.Fatal(err)
    }

    // Get the process ID (PID) of the child process
    pid := cmd.Process.Pid

    // Print the PID
    fmt.Printf("PID: %d\n", pid)

    // Read from the stdout and stderr pipes and log the output
    go func() {
        for {
            buf := make([]byte, 1024)
            n, err := stdoutPipe.Read(buf)
            if err != nil {
                log.Fatal(err)
            }
            fmt.Printf("stdout: %s", string(buf[:n]))
        }
    }()
    go func() {
        for {
            buf := make([]byte, 1024)
            n, err := stderrPipe.Read(buf)
            if err != nil {
                log.Fatal(err)
            }
            fmt.Printf("stderr: %s", string(buf[:n]))
        }
    }()

    // Wait for the command to finish
    if err := cmd.Wait(); err != nil {
        if exitErr := cmd.ProcessState.Sys().(syscall.WaitStatus).ExitStatus(); exitErr != 0 {
            log.Fatal(fmt.Sprintf("Error #48692663: Command exited with code %d", exitErr))
        } else {
            log.Printf("Command exited with exit code 0")
        }
    }

    // Optionally, keep the child process alive even after the parent process exits
    // This can be achieved by setting `cmd.SysProcAttr = &syscall.SysProcAttr{Setpgid: true}` before starting the command.

    // Example of sending a signal to the detached process
    if err := syscall.Kill(pid, os.Interrupt); err != nil {
        log.Fatalf("Error sending signal to process: %d: %s", pid, err)
    } else {
        fmt.Printf("Received ^C and forwarded to process %d\n", pid)
    }

    // Optionally, use `syscall.Reap()` to clean up any child processes that are terminated but not yet waited for.
}</code>

This code demonstrates how to execute a command in a detached manner, allowing it to continue running independently of the parent process. It provides features such as capturing stdout and stderr, obtaining the process ID, and optionally sending signals to the child process.

Key Considerations:

  • Note that detaching a process does not prevent it from becoming orphaned upon the exit of its parent, as the kernel still holds a reference to it.
  • Using SysProcAttr.Setpgid can keep the child process alive independently, but it may require additional handling in certain cases.
  • Be sure to use Wait() to ensure that the process returns an exit code and you can handle any potential errors.
  • Use syscall.Reap() to clean up zombie processes to avoid resource leaks.

The above is the detailed content of How to Execute a Command in Go and Detach It from the Parent Process?. For more information, please follow other related articles on the PHP Chinese website!

Statement
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
Go language pack import: What is the difference between underscore and without underscore?Go language pack import: What is the difference between underscore and without underscore?Mar 03, 2025 pm 05:17 PM

This article explains Go's package import mechanisms: named imports (e.g., import "fmt") and blank imports (e.g., import _ "fmt"). Named imports make package contents accessible, while blank imports only execute t

How to implement short-term information transfer between pages in the Beego framework?How to implement short-term information transfer between pages in the Beego framework?Mar 03, 2025 pm 05:22 PM

This article explains Beego's NewFlash() function for inter-page data transfer in web applications. It focuses on using NewFlash() to display temporary messages (success, error, warning) between controllers, leveraging the session mechanism. Limita

How to convert MySQL query result List into a custom structure slice in Go language?How to convert MySQL query result List into a custom structure slice in Go language?Mar 03, 2025 pm 05:18 PM

This article details efficient conversion of MySQL query results into Go struct slices. It emphasizes using database/sql's Scan method for optimal performance, avoiding manual parsing. Best practices for struct field mapping using db tags and robus

How do I write mock objects and stubs for testing in Go?How do I write mock objects and stubs for testing in Go?Mar 10, 2025 pm 05:38 PM

This article demonstrates creating mocks and stubs in Go for unit testing. It emphasizes using interfaces, provides examples of mock implementations, and discusses best practices like keeping mocks focused and using assertion libraries. The articl

How can I define custom type constraints for generics in Go?How can I define custom type constraints for generics in Go?Mar 10, 2025 pm 03:20 PM

This article explores Go's custom type constraints for generics. It details how interfaces define minimum type requirements for generic functions, improving type safety and code reusability. The article also discusses limitations and best practices

How to write files in Go language conveniently?How to write files in Go language conveniently?Mar 03, 2025 pm 05:15 PM

This article details efficient file writing in Go, comparing os.WriteFile (suitable for small files) with os.OpenFile and buffered writes (optimal for large files). It emphasizes robust error handling, using defer, and checking for specific errors.

How do you write unit tests in Go?How do you write unit tests in Go?Mar 21, 2025 pm 06:34 PM

The article discusses writing unit tests in Go, covering best practices, mocking techniques, and tools for efficient test management.

How can I use tracing tools to understand the execution flow of my Go applications?How can I use tracing tools to understand the execution flow of my Go applications?Mar 10, 2025 pm 05:36 PM

This article explores using tracing tools to analyze Go application execution flow. It discusses manual and automatic instrumentation techniques, comparing tools like Jaeger, Zipkin, and OpenTelemetry, and highlighting effective data visualization

See all articles

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

AI Hentai Generator

AI Hentai Generator

Generate AI Hentai for free.

Hot Article

R.E.P.O. Energy Crystals Explained and What They Do (Yellow Crystal)
2 weeks agoBy尊渡假赌尊渡假赌尊渡假赌
Repo: How To Revive Teammates
1 months agoBy尊渡假赌尊渡假赌尊渡假赌
Hello Kitty Island Adventure: How To Get Giant Seeds
4 weeks agoBy尊渡假赌尊渡假赌尊渡假赌

Hot Tools

Safe Exam Browser

Safe Exam Browser

Safe Exam Browser is a secure browser environment for taking online exams securely. This software turns any computer into a secure workstation. It controls access to any utility and prevents students from using unauthorized resources.

SublimeText3 Linux new version

SublimeText3 Linux new version

SublimeText3 Linux latest version

VSCode Windows 64-bit Download

VSCode Windows 64-bit Download

A free and powerful IDE editor launched by Microsoft

Atom editor mac version download

Atom editor mac version download

The most popular open source editor

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)