How to fork a process

Question

I need help understanding how to demonize a process in Go.

package main

import (
   "fmt"
   "os"
)

func start() {
   var procAttr os.ProcAttr 
   procAttr.Files = []*os.File{nil, nil, nil}
   _, err := os.StartProcess("/Path/prog", nil, &procAttr)
   if err != nil {
       fmt.Printf("%v", err)
   }
}


func main () {
   start()
} 

If you start this code on the command line the program returns control, but is still connected with cmd. Closing the cmd closes the program.

How can I decouple it from the cmd? Adding:

procAttr.Sys.HideWindow = true

Results in this error: "panic" to wrong memory pointer

Answer 1

I asked in 'golang-nuts', and found out that Go has a link option:

go tool 8l -o output.exe -Hwindowsgui input.8

Answer 2

Here is a fake daemon in go; it's simple to use: https://github.com/icattlecoder/godaemon

An example:

package main

import (
    _ "github.com/icattlecoder/godaemon"
    "log"
    "net/http"
)

func main() {
    mux := http.NewServeMux()
    mux.HandleFunc("/index", func(rw http.ResponseWriter, req *http.Request) {
        rw.Write([]byte("hello, golang!\n"))
    })
    log.Fatalln(http.ListenAndServe(":7070", mux))
}