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Forum Update on Monday, May 27th 2025

Running Qt Example client/server not working

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  • K kshegunov
    19 Jul 2016, 18:19

    @marlenet15
    That's strange. Is it possible the connection times out? What happens if you wait a little? Could you check (if running on windows for example) that there's no system tool that interferes with the network connection?

    Kind regards.

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    marlenet15
    wrote on 19 Jul 2016, 18:33 last edited by
    #5

    @kshegunov I have been waiting for at least 5 minutes and nothing happens. I am running Qt on Linux and I don't think anything is interfering it.

    1 Reply Last reply
    0
    • M marlenet15
      19 Jul 2016, 18:16

      It does not crash. After I click the button "get fortune", nothing happens. From what I read in the code, if the client was not able to find the server then it would output that it was not able to find it. However, I get no errors back at all.

      M Offline
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      mrjj
      Lifetime Qt Champion
      wrote on 19 Jul 2016, 18:34 last edited by mrjj
      #6

      @marlenet15

      Hi
      The IP the server find/shows might not be valid.
      for me it was not. (just ran the samples)
      use localhost for client
      and it works for me.

      That ip is not my local IP, nor my wan.
      No interface seems to have it.

      So be sure the IP it shows is correct :)

      M 1 Reply Last reply 19 Jul 2016, 18:53
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      • M mrjj
        19 Jul 2016, 18:34

        @marlenet15

        Hi
        The IP the server find/shows might not be valid.
        for me it was not. (just ran the samples)
        use localhost for client
        and it works for me.

        That ip is not my local IP, nor my wan.
        No interface seems to have it.

        So be sure the IP it shows is correct :)

        M Offline
        M Offline
        marlenet15
        wrote on 19 Jul 2016, 18:53 last edited by
        #7

        @mrjj On terminal I ran ifconfig and under wlan it shows the ip address that is shown on the fortune server. So what you are using is to use 127.0.0.1 on the client and server side as the ip address? Because that doesn't work either. :/

        M 1 Reply Last reply 19 Jul 2016, 18:57
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        • M marlenet15
          19 Jul 2016, 18:53

          @mrjj On terminal I ran ifconfig and under wlan it shows the ip address that is shown on the fortune server. So what you are using is to use 127.0.0.1 on the client and server side as the ip address? Because that doesn't work either. :/

          M Offline
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          mrjj
          Lifetime Qt Champion
          wrote on 19 Jul 2016, 18:57 last edited by mrjj
          #8

          @marlenet15
          Ok so in linux it find right ip I guess. ( im on win)
          yes local host is that 127.x.x.x ip.
          And i use it for server IP. + the listed port.

          Are u running both samples on same machine?

          It works here both for win 7 and win 10.

          M 1 Reply Last reply 19 Jul 2016, 19:09
          1
          • M mrjj
            19 Jul 2016, 18:57

            @marlenet15
            Ok so in linux it find right ip I guess. ( im on win)
            yes local host is that 127.x.x.x ip.
            And i use it for server IP. + the listed port.

            Are u running both samples on same machine?

            It works here both for win 7 and win 10.

            M Offline
            M Offline
            marlenet15
            wrote on 19 Jul 2016, 19:09 last edited by
            #9

            @mrjj I am doing exactly as you are telling me but nothing. Also, I am using Threaded Fortune Server. Are you using that as well?

            So in my Threaded Fortune Server I have :
            IP: 192.168.1.209
            port: 45127

            In my fortune client I have:
            Server name: localhost
            port: 45127

            M K 2 Replies Last reply 19 Jul 2016, 19:26
            0
            • M marlenet15
              19 Jul 2016, 19:09

              @mrjj I am doing exactly as you are telling me but nothing. Also, I am using Threaded Fortune Server. Are you using that as well?

              So in my Threaded Fortune Server I have :
              IP: 192.168.1.209
              port: 45127

              In my fortune client I have:
              Server name: localhost
              port: 45127

              M Offline
              M Offline
              mrjj
              Lifetime Qt Champion
              wrote on 19 Jul 2016, 19:26 last edited by
              #10

              @marlenet15
              nope, im using the "simple" ones.

              local host should work if both server and client is run on same machine.

              I will check tomorrow when i have a linux to see.

              1 Reply Last reply
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              • M marlenet15
                19 Jul 2016, 19:09

                @mrjj I am doing exactly as you are telling me but nothing. Also, I am using Threaded Fortune Server. Are you using that as well?

                So in my Threaded Fortune Server I have :
                IP: 192.168.1.209
                port: 45127

                In my fortune client I have:
                Server name: localhost
                port: 45127

                K Offline
                K Offline
                kshegunov
                Moderators
                wrote on 19 Jul 2016, 19:35 last edited by
                #11

                @marlenet15
                That's really, really strange. Could you run the client code through the debugger? What would be the TCP error the client gets?
                (I don't have Qt 4 to test, sorry).

                Kind regards.

                Read and abide by the Qt Code of Conduct

                M 1 Reply Last reply 19 Jul 2016, 19:55
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                • K kshegunov
                  19 Jul 2016, 19:35

                  @marlenet15
                  That's really, really strange. Could you run the client code through the debugger? What would be the TCP error the client gets?
                  (I don't have Qt 4 to test, sorry).

                  Kind regards.

                  M Offline
                  M Offline
                  marlenet15
                  wrote on 19 Jul 2016, 19:55 last edited by
                  #12

                  @kshegunov Ok So I used the regular Fortune Server and it works. So I am wondering why with the Threaded Fortune Server it does not work. The thing is I need to use threaded server.

                  K 1 Reply Last reply 19 Jul 2016, 20:11
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                  • M marlenet15
                    19 Jul 2016, 19:55

                    @kshegunov Ok So I used the regular Fortune Server and it works. So I am wondering why with the Threaded Fortune Server it does not work. The thing is I need to use threaded server.

                    K Offline
                    K Offline
                    kshegunov
                    Moderators
                    wrote on 19 Jul 2016, 20:11 last edited by
                    #13

                    @marlenet15 said:

                    So I am wondering why with the Threaded Fortune Server it does not work. The thing is I need to use threaded server.

                    Well, perhaps the example is broken; it has happened. But in any case the threaded fortune server is not really a good example of a threaded TCP server, not for real work anyway.

                    Kind regards.

                    Read and abide by the Qt Code of Conduct

                    M 1 Reply Last reply 19 Jul 2016, 20:20
                    1
                    • K kshegunov
                      19 Jul 2016, 20:11

                      @marlenet15 said:

                      So I am wondering why with the Threaded Fortune Server it does not work. The thing is I need to use threaded server.

                      Well, perhaps the example is broken; it has happened. But in any case the threaded fortune server is not really a good example of a threaded TCP server, not for real work anyway.

                      Kind regards.

                      M Offline
                      M Offline
                      marlenet15
                      wrote on 19 Jul 2016, 20:20 last edited by
                      #14

                      @kshegunov Do you know of any good examples? Thank you.

                      K 1 Reply Last reply 19 Jul 2016, 20:34
                      0
                      • M marlenet15
                        19 Jul 2016, 20:20

                        @kshegunov Do you know of any good examples? Thank you.

                        K Offline
                        K Offline
                        kshegunov
                        Moderators
                        wrote on 19 Jul 2016, 20:34 last edited by
                        #15

                        @marlenet15
                        Honestly, no. But I was about to write something as an example for a library of mine, so I'll post when I have it.
                        Meanwhile, you should look up how to use the asynchronous TCP socket API in Qt and make your code work in single thread. Look here for example. When that's done it takes very little modification to make it work in multiple threads.

                        Kind regards.

                        Read and abide by the Qt Code of Conduct

                        M 1 Reply Last reply 19 Jul 2016, 20:53
                        1
                        • K kshegunov
                          19 Jul 2016, 20:34

                          @marlenet15
                          Honestly, no. But I was about to write something as an example for a library of mine, so I'll post when I have it.
                          Meanwhile, you should look up how to use the asynchronous TCP socket API in Qt and make your code work in single thread. Look here for example. When that's done it takes very little modification to make it work in multiple threads.

                          Kind regards.

                          M Offline
                          M Offline
                          marlenet15
                          wrote on 19 Jul 2016, 20:53 last edited by
                          #16

                          @kshegunov Thank you so much!

                          K 1 Reply Last reply 21 Jul 2016, 22:13
                          0
                          • M marlenet15
                            19 Jul 2016, 20:53

                            @kshegunov Thank you so much!

                            K Offline
                            K Offline
                            kshegunov
                            Moderators
                            wrote on 21 Jul 2016, 22:13 last edited by kshegunov
                            #17

                            @marlenet15
                            Hi,
                            Here you can find a threaded TCP server example. You can ignore the module specific classes QDaemonApplication (think of it as QCoreApplication) and QDaemonLog you can substitute with QDebug.

                            Enjoy!
                            Kind regards.

                            Read and abide by the Qt Code of Conduct

                            1 Reply Last reply
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                            19 Jul 2016, 20:20

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