You really should ‘panic on err’ when diagnosing these sort of issues - because I need the full error information.
That being said, if you ‘Connect()’ then many times you can’t use Sendto(), you need to use Send() - or don’t Connect(). When you “Connect” you are connecting the socket which controls the destination for packets. > On Feb 15, 2020, at 5:25 PM, Gert <[email protected]> wrote: > > Another attempt but now I get `socket is already connected` > > https://play.golang.org/p/-klJZPnKFRk <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 > <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 <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 <[email protected] <>> wrote: >> >> >> Sorry. I missed the part about “domain” socket. >> >>> On Feb 15, 2020, at 9:26 AM, Robert Engels <[email protected] <>> wrote: >>> >>> >>> See github.com/robaho/go-trader <http://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 <[email protected] <>> 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, (structsockaddr*) &client, &len) >>>> sendto(fd, buff, strlen(buff)+1, 0,(struct sockaddr*) &client, len) >>>> >>>> My socket knowledge is limited and https://golang.org/pkg/net/ >>>> <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 [email protected] <>. >>>> 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 [email protected] > <mailto:[email protected]>. > To view this discussion on the web visit > https://groups.google.com/d/msgid/golang-nuts/a2c197f9-ceb2-49d7-af4d-f8485a5b69ba%40googlegroups.com > > <https://groups.google.com/d/msgid/golang-nuts/a2c197f9-ceb2-49d7-af4d-f8485a5b69ba%40googlegroups.com?utm_medium=email&utm_source=footer>. -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. 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