为什么80%的码农都做不了架构师？>>> 
Go 语言net/http 包使用模式
监听多个端口：
func handler2(w http.ResponseWriter, r *http.Request) {
fmt.Fprintf(w, "Hello, HTTP Server1")
}
func handler1(w http.ResponseWriter, r *http.Request) {
fmt.Fprintf(w, "Hello, HTTP Server2")
}
func main() {
go func(){
mux := http.NewServeMux()
mux.HandleFunc("/", handler2)
http.ListenAndServe(":1234", mux)
}()
mux := http.NewServeMux()
mux.HandleFunc("/", handler1)
http.ListenAndServe(":12345", mux)
}