import ( "log" "net/rpc" ) type Args struct { X, Y int } func main() { client, err := rpc.DialHTTP("tcp", "localhost:1234") if err != nil { log.Fatal("dialing:", err) } // Synchronous call args := Args{7,8} var reply int err = client.Call("Arith.Multiply", args, &reply) if err != nil { log.Fatal("arith error:", err) } fmt.Printf("Arith: %d*%d=%d", args.X, args.Y, reply) // Asynchronous call divCall := client.Go("Arith.Divide", args, &reply, nil) replyCall := <-divCall.Done if replyCall.Error != nil { log.Fatal("arith error:", replyCall.Error.Error()) // Response Error } fmt.Printf("Arith: %d/%d=%d", args.X, args.Y, reply) client.Close() }In this example, we use the net/rpc package to make two RPC calls to a service named Arith. The first call is made synchronously using the Call function, while the second call is made asynchronously using the Go function. If an error occurs during the RPC call, a Response Error is returned and can be accessed through `replyCall.Error.Error()`. The Response Error struct is part of the net/rpc package in Go.