Another attempt but now I get `socket is already connected` https://play.golang.org/p/-klJZPnKFRk
On Saturday, February 15, 2020 at 8:53:46 PM UTC+1, Gert wrote: > > Thx when looking for Recv() and Send() I found this package > https://pkg.go.dev/golang.org/x/sys/unix > > I don't understand how I'm suppose to create a new SockaddrUnix when raw > is a private field? > > https://play.golang.org/p/fe1f_A92BgI > > Also don't know if my strcpy is the way to fill in path? > > On Saturday, February 15, 2020 at 4:31:00 PM UTC+1, Robert Engels wrote: >> >> You want to use Recv() and Send() not Read() and Write() in order to get >> the address information. >> >> Read() and Write() are for connected sockets and usually streaming. >> >> On Feb 15, 2020, at 9:27 AM, Robert Engels <ren...@ix.netcom.com> wrote: >> >> >> Sorry. I missed the part about “domain” socket. >> >> On Feb 15, 2020, at 9:26 AM, Robert Engels <ren...@ix.netcom.com> wrote: >> >> >> See github.com/robaho/go-trader for an example of sending / receiving >> udp traffic. There’s no reason to use the low level Unix interfaces. >> >> On Feb 15, 2020, at 9:22 AM, Gert <gert....@gmail.com> wrote: >> >> >> Hi, leaving out a lot of details I basically do this in a C client >> >> fd = socket(PF_UNIX, SOCK_DGRAM, 0) >> bind(fd, (struct sockaddr*) &client, sizeof(struct sockaddr_un) >> connect(fd, (struct sockaddr*) &server, sizeof(struct sockaddr_un) >> send(fd, buff, strlen(buff)+1, 0) >> recv(fd, buff, 8192, 0) >> >> Which means I have a client socket where I receive datagrams and a server >> socket where I sent datagrams to. >> >> It works in my C client above but having troubles understanding how to >> talk to the same C server using a Go client instead. This is my attempt >> >> >> addr, err := net.ResolveUnixAddr("unixgram", "client.sock") >> if err != nil { >> log.Fatal(err) >> } >> >> client, err := net.ListenUnixgram("unixgram", addr) >> if err != nil { >> log.Fatal(err) >> } >> defer client.Close() >> >> server, err := net.Dial("unixgram", "server.sock") >> if err != nil { >> log.Fatal(err) >> } >> defer server.Close() >> >> _, err = server.Write([]byte("hi")) >> if err != nil { >> log.Fatal(err) >> } >> >> buf := make([]byte, 1024) >> n, err := client.Read(buf[:]) >> if err != nil { >> println(err) >> } >> println(string(buf[0:n])) >> >> if err := os.RemoveAll("client.sock"); err != nil { >> log.Fatal(err) >> } >> >> >> What happens in the Go implementation is that it successfully send a >> datagram, the server receives it but then the server can't figure out where >> to send a answer back with a error from the server sendto: `No such file or >> directory` >> >> This is basically what the the C server code is doing. >> >> recvfrom(fd, buff, 8192, 0, (struct sockaddr*) &client, &len) >> sendto(fd, buff, strlen(buff)+1, 0, (struct sockaddr*) &client, len) >> >> My socket knowledge is limited and https://golang.org/pkg/net/ is >> overwhelming, if I would make a guess is that de C client shares fd between >> bind and connect and my Go implementation doesn't ? >> >> >> -- >> 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 golan...@googlegroups.com. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/golang-nuts/644fa128-96c9-47f8-abc5-5fcc19d01e6e%40googlegroups.com >> >> <https://groups.google.com/d/msgid/golang-nuts/644fa128-96c9-47f8-abc5-5fcc19d01e6e%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> >> -- 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. To view this discussion on the web visit https://groups.google.com/d/msgid/golang-nuts/a2c197f9-ceb2-49d7-af4d-f8485a5b69ba%40googlegroups.com.
