package main import ( "fmt" "os" "strings" ) func main() { if len(os.Args) < 2 { fmt.Println() fmt.Printf("Usage: %s MODE [OPTIONS]\n\n"+ "Modes: server / client\n"+ "Use -h to see the available options for a mode.\n\n", os.Args[0]) return } mode := strings.ToLower(strings.TrimSpace(os.Args[1])) switch mode { case "server", "s": server(os.Args[2:]) case "client", "c": client(os.Args[2:]) default: fmt.Println("Invalid mode:", mode) } }