GoLang project CMD command have strange behave

I'm working on a GoLang Project for Rosetta-API.
There is a implementation for exec.Command

Code:

    func StartBitcoind(ctx context.Context, configPath string, g *errgroup.Group) error {
	logger := utils.ExtractLogger(ctx, "eunod")
	cmd := exec.Command(
		"/app/eunod",
		fmt.Sprintf("--conf=%s", configPath),
	)

	stdout, err := cmd.StdoutPipe()
	if err != nil {
		return err
	}

	stderr, err := cmd.StderrPipe()
	if err != nil {
		return err
	}

	g.Go(func() error {
		return logPipe(ctx, stdout, bitcoindLogger)
	})

	g.Go(func() error {
		return logPipe(ctx, stderr, bitcoindStdErrLogger)
	})

	if err := cmd.Start(); err != nil {
		return fmt.Errorf("%w: unable to start eunod", err)
	}

	g.Go(func() error {
		<-ctx.Done()

		logger.Warnw("sending interrupt to eunod")
		return cmd.Process.Signal(os.Interrupt)
	})

	return cmd.Wait()
}

From now i will linked to github.

On line: https://github.com/ScArFaCe2020/rosetta-euno/blob/master/bitcoin/node.go#L68-L71 is the exec.Command.

the fmt.Sprintf("--conf=%s", configPath), Works fine.
Now i need to add --daemon inside it.

But when i change this to

fmt.Sprintf("--daemon --conf=%s", configPath),

It doesn't work.

Does anyone have a idea how i can add the --daemon?

exec.Command takes variadic string arguments. Its signature looks like this.

func Command(name string, arg ...string) *Cmd

Either pass a slice of stings followed by ... or pass a number of strings as arguments.

In your case, you treat the whole string --daemon --conf=/some/path as a single argument, while you actually want to treat it as two distinct arguments.

The most simple way to solve this would be doing it like this.

cmd := exec.Command(
    "/app/eunod",
    "--daemon",
    fmt.Sprintf("--conf=%s", configPath),
)

You can learn more about variadic arguments here https://golangdocs.com/variadic-functions-in-golang for example.