Test of running multiple HTTP listeners.

exeuction.sh

bash-3.2$ curl -v http://localhost:8080/bar && echo
*   Trying ::1...
* TCP_NODELAY set
* Connected to localhost (::1) port 8080 (#0)
> GET /bar HTTP/1.1
> Host: localhost:8080
> User-Agent: curl/7.54.0
> Accept: */*
>
< HTTP/1.1 200 OK
< Date: Fri, 23 Feb 2018 12:06:35 GMT
< Content-Length: 13
< Content-Type: text/plain; charset=utf-8
<
* Connection #0 to host localhost left intact
Hello, "/bar"
bash-3.2$ curl -v http://localhost:8081/bar && echo
*   Trying ::1...
* TCP_NODELAY set
* Connection failed
* connect to ::1 port 8081 failed: Connection refused
*   Trying 127.0.0.1...
* TCP_NODELAY set
* Connection failed
* connect to 127.0.0.1 port 8081 failed: Connection refused
* Failed to connect to localhost port 8081: Connection refused
* Closing connection 0
curl: (7) Failed to connect to localhost port 8081: Connection refused

multihttp.go

package main

import (
	"fmt"
	"html"
	"log"
	"net/http"
)

func main() {
	http.HandleFunc("/bar", func(w http.ResponseWriter, r *http.Request) {
		fmt.Fprintf(w, "Hello, %q", html.EscapeString(r.URL.Path))
	})
	go log.Fatal(http.ListenAndServe(":8080", nil))
	log.Fatal(http.ListenAndServe(":8081", nil))
}