golang open url in default browser

url_open.go

// https://stackoverflow.com/questions/39320371/how-start-web-server-to-open-page-in-browser-in-golang
// open opens the specified URL in the default browser of the user.
func open(url string) error {
    var cmd string
    var args []string

    switch runtime.GOOS {
    case "windows":
        cmd = "cmd"
        args = []string{"/c", "start"}
    case "darwin":
        cmd = "open"
    default: // "linux", "freebsd", "openbsd", "netbsd"
        cmd = "xdg-open"
    }
    args = append(args, url)
    return exec.Command(cmd, args...).Start()
}

small fix

case "windows":
	cmd = "cmd"
	args = []string{"/c", "start" , url}  // added missing "url" param