UDP Server's code:
package main
import (
"fmt"
"net"
)
func main() {
listener, err := net.ListenUDP("udp", &net.UDPAddr{IP:
net.ParseIP("127.0.0.1"), Port: 9981})
if err != nil {
fmt.Println(err)
return
}
fmt.Printf("Local: <%s> \n", listener.LocalAddr().String())
data := make([]byte, 1024)
for {
n, remoteAddr, err := listener.ReadFromUDP(data)
if err != nil {
fmt.Printf("error during read: %s", err)
}
fmt.Printf("<%s> %s\n", remoteAddr, data[:n])
_, err = listener.WriteToUDP(data[0:n], remoteAddr)
_, err = listener.WriteToUDP([]byte("world"), remoteAddr)
if err != nil {
fmt.Printf(err.Error())
}
}
}
UDP Client's Code:
package main
import (
"fmt"
"net"
"bytes"
)
func main() {
ip := net.ParseIP("127.0.0.1")
srcAddr := &net.UDPAddr{IP: net.IPv4zero, Port: 0}
dstAddr := &net.UDPAddr{IP: ip, Port: 9981}
conn, err := net.DialUDP("udp", srcAddr, dstAddr)
if err != nil {
fmt.Println(err)
}
defer conn.Close()
conn.Write([]byte("hello"))
buff := bytes.NewBuffer(make([]byte, 3))
fmt.Println(buff.ReadFrom(conn))
fmt.Printf("<%s>\n", conn.RemoteAddr())
}
Why the UDP client blocked using BuffReadFrom method when read from a UDP
connection?
However, using bufio's Reader(the code is below) is ok.
I am a newbie, feel really confused, so can anybody give me some
explanation, thanks!
My running environment is macOS Sierra and go version is go1.8.3
darwin/amd64
package main
import (
"fmt"
"net"
"bufio"
)
func main() {
ip := net.ParseIP("127.0.0.1")
srcAddr := &net.UDPAddr{IP: net.IPv4zero, Port: 0}
dstAddr := &net.UDPAddr{IP: ip, Port: 9981}
conn, err := net.DialUDP("udp", srcAddr, dstAddr)
if err != nil {
fmt.Println(err)
}
defer conn.Close()
conn.Write([]byte("hello"))
reader := bufio.NewReader(conn)
rawbuff := make([]byte, 64)
fmt.Println(reader.Read(rawbuff))
fmt.Println(string(rawbuff))
fmt.Printf("<%s>\n", conn.RemoteAddr())
}
--
You received this message because you are subscribed to the Google Groups
"golang-nuts" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to golang-nuts+unsubscr...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.
