Minimalistic one-way TCP chat in Golang

server.go

package main

import (
	"fmt"
	"log"
	"net"
)

var send = make(chan string)

var id = 1

type Session struct {
	MaxClients int
	Clients    int
	Users      []User
}

type User struct {
	Nickname int
	IP       string
	Conn     net.Conn
}

func (u *User) Listen() {
	for {
		b := make([]byte, 1024)
		u.Conn.Read(b)

		send <- fmt.Sprintf("%d", u.Nickname) + ": " + string(b[:])
	}
}

func CreateUser(conn net.Conn) User {
	usr := User{id, conn.RemoteAddr().String(), conn}
	id++

	go usr.Listen()

	return usr
}

func checkerr(err error) {
	if err != nil {
		panic(err)
	}
}

func main() {
	c := 10
	session := Session{c, 0, make([]User, 0)}

	listener, err := net.Listen("tcp", ":4444")
	checkerr(err)

	go func() {
		for {
			conn, err := listener.Accept()
			checkerr(err)

			if session.Clients >= session.MaxClients {
				conn.Write([]byte("Participant limit reached.\n"))
				conn.Close()
				break
			} else {
				log.Printf("User %s joined.\n", conn.RemoteAddr().String())
			}

			session.Users = append(session.Users, CreateUser(conn))
		}
	}()

	var msg string

	for {
		msg = <-send
		for _, u := range session.Users {
			u.Conn.Write([]byte(msg))
		}
	}
}