How to create hardlinks recursively?

Question

If I were to do it on Linux alone, it'd be easy with the following code:

package main

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

func main() {

    err := exec.Command("cp", "-rl", "src/path", "target/path").Run()
    if err != nil {
        log.Fatal(err)
    }
}

However, I am looking for a way to do so in Golang so that it works across different operating systems.

Answer 1

It's really depends on the underling filesystem that support for linking a file or not. but below is the code snippet that i think works for the most OS (tested on macOS and ubuntu 20.04)

package main

import (
    "fmt"
    "io/fs"
    "log"
    "os"
    "path/filepath"
)

func main() {
    err := filepath.WalkDir("src/path", func(path string, d fs.DirEntry, err error) error {
        if err != nil {
            log.Fatal(err)
        }
        if d.IsDir() {
            return nil
        }
        destinationFile := fmt.Sprintf("/target/%s", path)
        err = os.Link(path, destinationFile)
        if err != nil {
            log.Fatal(err)
        }
        return nil
    })
    if err != nil {
        log.Fatal(err)
    }
}