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[Windows] First QUdpSocket::bind blocks for three seconds

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  • SGaistS Offline
    SGaistS Offline
    SGaist
    Lifetime Qt Champion
    wrote on last edited by
    #7

    @dheerendra They are not useless. These are self assigned IP which are used when you connect directly devices together without any dhcp server between them e.g. direct cable connection from your computer to a network camera.

    You can then use something like zeroconf to find the devices (if they do advertise something using that protocol).

    Interested in AI ? www.idiap.ch
    Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

    1 Reply Last reply
    3
    • mrjjM Offline
      mrjjM Offline
      mrjj
      Lifetime Qt Champion
      wrote on last edited by
      #8

      Hi
      Its quite normal ips and the concept is called Automatic Private IP Addressing.
      https://wiki.wireshark.org/APIPA

      1 Reply Last reply
      0
      • dheerendraD Offline
        dheerendraD Offline
        dheerendra
        Qt Champions 2022
        wrote on last edited by dheerendra
        #9

        @SGaist as you said they are assigned without DHCP server. These are internally allocated and not known to user. This is where my point came as useless. IP addresses should be either statically assigned by user or configured from DHCP. Then these address will be usable.

        Dheerendra
        @Community Service
        Certified Qt Specialist
        http://www.pthinks.com

        1 Reply Last reply
        0
        • dheerendraD dheerendra

          IP address starting with 169.254.x.x are useless IP address. It is better you filter then bind them. These address indicates some configuration issue. Can you also run 'ifconfig /all command' and show me the output ? I'm wondering why so many 169.254... address on your box.

          aha_1980A Offline
          aha_1980A Offline
          aha_1980
          Lifetime Qt Champion
          wrote on last edited by
          #10

          @dheerendra

          You're right, there are a lot of IP addresses. I don't know why, I got the laptop in this state ;) But I'll try to filter them out.

          Here is the ifconfig output:

          
          Windows-IP-Konfiguration
          
             Hostname  . . . . . . . . . . . . : AHNB
             Primäres DNS-Suffix . . . . . . . : 
             Knotentyp . . . . . . . . . . . . : Hybrid
             IP-Routing aktiviert  . . . . . . : Nein
             WINS-Proxy aktiviert  . . . . . . : Nein
          
          Ethernet-Adapter Bluetooth-Netzwerkverbindung:
          
             Medienstatus. . . . . . . . . . . : Medium getrennt
             Verbindungsspezifisches DNS-Suffix: 
             Beschreibung. . . . . . . . . . . : Bluetooth-Gerät (PAN)
             Physikalische Adresse . . . . . . : AC-2B-6E-DB-86-C9
             DHCP aktiviert. . . . . . . . . . : Ja
             Autokonfiguration aktiviert . . . : Ja
          
          Drahtlos-LAN-Adapter Drahtlosnetzwerkverbindung 3:
          
             Medienstatus. . . . . . . . . . . : Medium getrennt
             Verbindungsspezifisches DNS-Suffix: 
             Beschreibung. . . . . . . . . . . : Microsoft Virtual WiFi Miniport Adapter #2
             Physikalische Adresse . . . . . . : AE-2B-6E-DB-86-C5
             DHCP aktiviert. . . . . . . . . . : Ja
             Autokonfiguration aktiviert . . . : Ja
          
          Drahtlos-LAN-Adapter Drahtlosnetzwerkverbindung 2:
          
             Medienstatus. . . . . . . . . . . : Medium getrennt
             Verbindungsspezifisches DNS-Suffix: 
             Beschreibung. . . . . . . . . . . : Microsoft Virtual WiFi Miniport Adapter
             Physikalische Adresse . . . . . . : AE-2B-6E-DB-86-C6
             DHCP aktiviert. . . . . . . . . . : Ja
             Autokonfiguration aktiviert . . . : Ja
          
          Drahtlos-LAN-Adapter Drahtlosnetzwerkverbindung:
          
             Medienstatus. . . . . . . . . . . : Medium getrennt
             Verbindungsspezifisches DNS-Suffix: wifirst.net
             Beschreibung. . . . . . . . . . . : Intel(R) Dual Band Wireless-AC 3165
             Physikalische Adresse . . . . . . : AC-2B-6E-DB-86-C5
             DHCP aktiviert. . . . . . . . . . : Ja
             Autokonfiguration aktiviert . . . : Ja
          
          Ethernet-Adapter LAN-Verbindung:
          
             Verbindungsspezifisches DNS-Suffix: 
             Beschreibung. . . . . . . . . . . : Intel(R) Ethernet Connection I219-V
             Physikalische Adresse . . . . . . : C8-5B-76-20-29-F1
             DHCP aktiviert. . . . . . . . . . : Nein
             Autokonfiguration aktiviert . . . : Ja
             Verbindungslokale IPv6-Adresse  . : fe80::9973:92be:7a06:90d2%11(Bevorzugt) 
             IPv4-Adresse  . . . . . . . . . . : 192.168.16.56(Bevorzugt) 
             Subnetzmaske  . . . . . . . . . . : 255.255.255.0
             IPv4-Adresse  . . . . . . . . . . : 192.168.25.56(Bevorzugt) 
             Subnetzmaske  . . . . . . . . . . : 255.255.255.0
             Standardgateway . . . . . . . . . : 192.168.25.1
             DHCPv6-IAID . . . . . . . . . . . : 248011638
             DHCPv6-Client-DUID. . . . . . . . : 00-01-00-01-1E-FA-29-B0-C8-5B-76-20-29-F1
             DNS-Server  . . . . . . . . . . . : 192.168.25.1
                                                 192.168.16.5
             NetBIOS über TCP/IP . . . . . . . : Aktiviert
          
          Ethernet-Adapter VirtualBox Host-Only Network:
          
             Verbindungsspezifisches DNS-Suffix: 
             Beschreibung. . . . . . . . . . . : VirtualBox Host-Only Ethernet Adapter
             Physikalische Adresse . . . . . . : 0A-00-27-00-00-1A
             DHCP aktiviert. . . . . . . . . . : Nein
             Autokonfiguration aktiviert . . . : Ja
             Verbindungslokale IPv6-Adresse  . : fe80::c876:59bb:672:4b63%26(Bevorzugt) 
             IPv4-Adresse  . . . . . . . . . . : 192.168.56.1(Bevorzugt) 
             Subnetzmaske  . . . . . . . . . . : 255.255.255.0
             Standardgateway . . . . . . . . . : 
             DHCPv6-IAID . . . . . . . . . . . : 722075687
             DHCPv6-Client-DUID. . . . . . . . : 00-01-00-01-1E-FA-29-B0-C8-5B-76-20-29-F1
             DNS-Server  . . . . . . . . . . . : fec0:0:0:ffff::1%1
                                                 fec0:0:0:ffff::2%1
                                                 fec0:0:0:ffff::3%1
             NetBIOS über TCP/IP . . . . . . . : Aktiviert
          
          Tunneladapter isatap.{67863029-37B5-4475-A830-A99108B681D0}:
          
             Medienstatus. . . . . . . . . . . : Medium getrennt
             Verbindungsspezifisches DNS-Suffix: 
             Beschreibung. . . . . . . . . . . : Microsoft-ISATAP-Adapter
             Physikalische Adresse . . . . . . : 00-00-00-00-00-00-00-E0
             DHCP aktiviert. . . . . . . . . . : Nein
             Autokonfiguration aktiviert . . . : Ja
          
          Tunneladapter isatap.{A1E35624-27B8-44CD-9F90-33505222FDC5}:
          
             Medienstatus. . . . . . . . . . . : Medium getrennt
             Verbindungsspezifisches DNS-Suffix: 
             Beschreibung. . . . . . . . . . . : Microsoft-ISATAP-Adapter #4
             Physikalische Adresse . . . . . . : 00-00-00-00-00-00-00-E0
             DHCP aktiviert. . . . . . . . . . : Nein
             Autokonfiguration aktiviert . . . : Ja
          
          Tunneladapter isatap.wifirst.net:
          
             Medienstatus. . . . . . . . . . . : Medium getrennt
             Verbindungsspezifisches DNS-Suffix: 
             Beschreibung. . . . . . . . . . . : Microsoft-ISATAP-Adapter #5
             Physikalische Adresse . . . . . . : 00-00-00-00-00-00-00-E0
             DHCP aktiviert. . . . . . . . . . : Nein
             Autokonfiguration aktiviert . . . : Ja
          
          Tunneladapter Teredo Tunneling Pseudo-Interface:
          
             Medienstatus. . . . . . . . . . . : Medium getrennt
             Verbindungsspezifisches DNS-Suffix: 
             Beschreibung. . . . . . . . . . . : Teredo Tunneling Pseudo-Interface
             Physikalische Adresse . . . . . . : 00-00-00-00-00-00-00-E0
             DHCP aktiviert. . . . . . . . . . : Nein
             Autokonfiguration aktiviert . . . : Ja
          
          Tunneladapter isatap.{8258A81F-8BED-473D-ACFA-857BDD793251}:
          
             Medienstatus. . . . . . . . . . . : Medium getrennt
             Verbindungsspezifisches DNS-Suffix: 
             Beschreibung. . . . . . . . . . . : Microsoft-ISATAP-Adapter #6
             Physikalische Adresse . . . . . . : 00-00-00-00-00-00-00-E0
             DHCP aktiviert. . . . . . . . . . : Nein
             Autokonfiguration aktiviert . . . : Ja
          
          Tunneladapter isatap.{EE03459F-FD31-4BF4-BF7E-7F3404F963B7}:
          
             Medienstatus. . . . . . . . . . . : Medium getrennt
             Verbindungsspezifisches DNS-Suffix: 
             Beschreibung. . . . . . . . . . . : Microsoft-ISATAP-Adapter #7
             Physikalische Adresse . . . . . . : 00-00-00-00-00-00-00-E0
             DHCP aktiviert. . . . . . . . . . : Nein
             Autokonfiguration aktiviert . . . : Ja
          
          Tunneladapter isatap.{5B651A37-F0DB-42B2-8109-C81D8A905622}:
          
             Medienstatus. . . . . . . . . . . : Medium getrennt
             Verbindungsspezifisches DNS-Suffix: 
             Beschreibung. . . . . . . . . . . : Microsoft-ISATAP-Adapter #8
             Physikalische Adresse . . . . . . : 00-00-00-00-00-00-00-E0
             DHCP aktiviert. . . . . . . . . . : Nein
             Autokonfiguration aktiviert . . . : Ja
          

          Qt has to stay free or it will die.

          aha_1980A 1 Reply Last reply
          0
          • aha_1980A aha_1980

            @dheerendra

            You're right, there are a lot of IP addresses. I don't know why, I got the laptop in this state ;) But I'll try to filter them out.

            Here is the ifconfig output:

            
            Windows-IP-Konfiguration
            
               Hostname  . . . . . . . . . . . . : AHNB
               Primäres DNS-Suffix . . . . . . . : 
               Knotentyp . . . . . . . . . . . . : Hybrid
               IP-Routing aktiviert  . . . . . . : Nein
               WINS-Proxy aktiviert  . . . . . . : Nein
            
            Ethernet-Adapter Bluetooth-Netzwerkverbindung:
            
               Medienstatus. . . . . . . . . . . : Medium getrennt
               Verbindungsspezifisches DNS-Suffix: 
               Beschreibung. . . . . . . . . . . : Bluetooth-Gerät (PAN)
               Physikalische Adresse . . . . . . : AC-2B-6E-DB-86-C9
               DHCP aktiviert. . . . . . . . . . : Ja
               Autokonfiguration aktiviert . . . : Ja
            
            Drahtlos-LAN-Adapter Drahtlosnetzwerkverbindung 3:
            
               Medienstatus. . . . . . . . . . . : Medium getrennt
               Verbindungsspezifisches DNS-Suffix: 
               Beschreibung. . . . . . . . . . . : Microsoft Virtual WiFi Miniport Adapter #2
               Physikalische Adresse . . . . . . : AE-2B-6E-DB-86-C5
               DHCP aktiviert. . . . . . . . . . : Ja
               Autokonfiguration aktiviert . . . : Ja
            
            Drahtlos-LAN-Adapter Drahtlosnetzwerkverbindung 2:
            
               Medienstatus. . . . . . . . . . . : Medium getrennt
               Verbindungsspezifisches DNS-Suffix: 
               Beschreibung. . . . . . . . . . . : Microsoft Virtual WiFi Miniport Adapter
               Physikalische Adresse . . . . . . : AE-2B-6E-DB-86-C6
               DHCP aktiviert. . . . . . . . . . : Ja
               Autokonfiguration aktiviert . . . : Ja
            
            Drahtlos-LAN-Adapter Drahtlosnetzwerkverbindung:
            
               Medienstatus. . . . . . . . . . . : Medium getrennt
               Verbindungsspezifisches DNS-Suffix: wifirst.net
               Beschreibung. . . . . . . . . . . : Intel(R) Dual Band Wireless-AC 3165
               Physikalische Adresse . . . . . . : AC-2B-6E-DB-86-C5
               DHCP aktiviert. . . . . . . . . . : Ja
               Autokonfiguration aktiviert . . . : Ja
            
            Ethernet-Adapter LAN-Verbindung:
            
               Verbindungsspezifisches DNS-Suffix: 
               Beschreibung. . . . . . . . . . . : Intel(R) Ethernet Connection I219-V
               Physikalische Adresse . . . . . . : C8-5B-76-20-29-F1
               DHCP aktiviert. . . . . . . . . . : Nein
               Autokonfiguration aktiviert . . . : Ja
               Verbindungslokale IPv6-Adresse  . : fe80::9973:92be:7a06:90d2%11(Bevorzugt) 
               IPv4-Adresse  . . . . . . . . . . : 192.168.16.56(Bevorzugt) 
               Subnetzmaske  . . . . . . . . . . : 255.255.255.0
               IPv4-Adresse  . . . . . . . . . . : 192.168.25.56(Bevorzugt) 
               Subnetzmaske  . . . . . . . . . . : 255.255.255.0
               Standardgateway . . . . . . . . . : 192.168.25.1
               DHCPv6-IAID . . . . . . . . . . . : 248011638
               DHCPv6-Client-DUID. . . . . . . . : 00-01-00-01-1E-FA-29-B0-C8-5B-76-20-29-F1
               DNS-Server  . . . . . . . . . . . : 192.168.25.1
                                                   192.168.16.5
               NetBIOS über TCP/IP . . . . . . . : Aktiviert
            
            Ethernet-Adapter VirtualBox Host-Only Network:
            
               Verbindungsspezifisches DNS-Suffix: 
               Beschreibung. . . . . . . . . . . : VirtualBox Host-Only Ethernet Adapter
               Physikalische Adresse . . . . . . : 0A-00-27-00-00-1A
               DHCP aktiviert. . . . . . . . . . : Nein
               Autokonfiguration aktiviert . . . : Ja
               Verbindungslokale IPv6-Adresse  . : fe80::c876:59bb:672:4b63%26(Bevorzugt) 
               IPv4-Adresse  . . . . . . . . . . : 192.168.56.1(Bevorzugt) 
               Subnetzmaske  . . . . . . . . . . : 255.255.255.0
               Standardgateway . . . . . . . . . : 
               DHCPv6-IAID . . . . . . . . . . . : 722075687
               DHCPv6-Client-DUID. . . . . . . . : 00-01-00-01-1E-FA-29-B0-C8-5B-76-20-29-F1
               DNS-Server  . . . . . . . . . . . : fec0:0:0:ffff::1%1
                                                   fec0:0:0:ffff::2%1
                                                   fec0:0:0:ffff::3%1
               NetBIOS über TCP/IP . . . . . . . : Aktiviert
            
            Tunneladapter isatap.{67863029-37B5-4475-A830-A99108B681D0}:
            
               Medienstatus. . . . . . . . . . . : Medium getrennt
               Verbindungsspezifisches DNS-Suffix: 
               Beschreibung. . . . . . . . . . . : Microsoft-ISATAP-Adapter
               Physikalische Adresse . . . . . . : 00-00-00-00-00-00-00-E0
               DHCP aktiviert. . . . . . . . . . : Nein
               Autokonfiguration aktiviert . . . : Ja
            
            Tunneladapter isatap.{A1E35624-27B8-44CD-9F90-33505222FDC5}:
            
               Medienstatus. . . . . . . . . . . : Medium getrennt
               Verbindungsspezifisches DNS-Suffix: 
               Beschreibung. . . . . . . . . . . : Microsoft-ISATAP-Adapter #4
               Physikalische Adresse . . . . . . : 00-00-00-00-00-00-00-E0
               DHCP aktiviert. . . . . . . . . . : Nein
               Autokonfiguration aktiviert . . . : Ja
            
            Tunneladapter isatap.wifirst.net:
            
               Medienstatus. . . . . . . . . . . : Medium getrennt
               Verbindungsspezifisches DNS-Suffix: 
               Beschreibung. . . . . . . . . . . : Microsoft-ISATAP-Adapter #5
               Physikalische Adresse . . . . . . : 00-00-00-00-00-00-00-E0
               DHCP aktiviert. . . . . . . . . . : Nein
               Autokonfiguration aktiviert . . . : Ja
            
            Tunneladapter Teredo Tunneling Pseudo-Interface:
            
               Medienstatus. . . . . . . . . . . : Medium getrennt
               Verbindungsspezifisches DNS-Suffix: 
               Beschreibung. . . . . . . . . . . : Teredo Tunneling Pseudo-Interface
               Physikalische Adresse . . . . . . : 00-00-00-00-00-00-00-E0
               DHCP aktiviert. . . . . . . . . . : Nein
               Autokonfiguration aktiviert . . . : Ja
            
            Tunneladapter isatap.{8258A81F-8BED-473D-ACFA-857BDD793251}:
            
               Medienstatus. . . . . . . . . . . : Medium getrennt
               Verbindungsspezifisches DNS-Suffix: 
               Beschreibung. . . . . . . . . . . : Microsoft-ISATAP-Adapter #6
               Physikalische Adresse . . . . . . : 00-00-00-00-00-00-00-E0
               DHCP aktiviert. . . . . . . . . . : Nein
               Autokonfiguration aktiviert . . . : Ja
            
            Tunneladapter isatap.{EE03459F-FD31-4BF4-BF7E-7F3404F963B7}:
            
               Medienstatus. . . . . . . . . . . : Medium getrennt
               Verbindungsspezifisches DNS-Suffix: 
               Beschreibung. . . . . . . . . . . : Microsoft-ISATAP-Adapter #7
               Physikalische Adresse . . . . . . : 00-00-00-00-00-00-00-E0
               DHCP aktiviert. . . . . . . . . . : Nein
               Autokonfiguration aktiviert . . . : Ja
            
            Tunneladapter isatap.{5B651A37-F0DB-42B2-8109-C81D8A905622}:
            
               Medienstatus. . . . . . . . . . . : Medium getrennt
               Verbindungsspezifisches DNS-Suffix: 
               Beschreibung. . . . . . . . . . . : Microsoft-ISATAP-Adapter #8
               Physikalische Adresse . . . . . . : 00-00-00-00-00-00-00-E0
               DHCP aktiviert. . . . . . . . . . : Nein
               Autokonfiguration aktiviert . . . : Ja
            
            aha_1980A Offline
            aha_1980A Offline
            aha_1980
            Lifetime Qt Champion
            wrote on last edited by
            #11

            Update: filtering the addresses starting with "169.254" did not help. It now stucks three seconds on my primary "192.168.16.56" IP address.

            Thanks also @J-Hilk, the order does not seem to matter...

            Qt has to stay free or it will die.

            1 Reply Last reply
            0
            • dheerendraD Offline
              dheerendraD Offline
              dheerendra
              Qt Champions 2022
              wrote on last edited by
              #12

              How about checking directly with calls like socket(...) & bind(..) call without using Qt ?

              Dheerendra
              @Community Service
              Certified Qt Specialist
              http://www.pthinks.com

              1 Reply Last reply
              0
              • dheerendraD Offline
                dheerendraD Offline
                dheerendra
                Qt Champions 2022
                wrote on last edited by
                #13

                Any reason you are calling bind(..) each time for each interfaces ? You can also try simple with passing QHostAddress::AnyIPv4 with just one bind call. This will allows the packet to coming from any interface.

                Dheerendra
                @Community Service
                Certified Qt Specialist
                http://www.pthinks.com

                aha_1980A 1 Reply Last reply
                0
                • dheerendraD dheerendra

                  Any reason you are calling bind(..) each time for each interfaces ? You can also try simple with passing QHostAddress::AnyIPv4 with just one bind call. This will allows the packet to coming from any interface.

                  aha_1980A Offline
                  aha_1980A Offline
                  aha_1980
                  Lifetime Qt Champion
                  wrote on last edited by
                  #14

                  @dheerendra

                  How about checking directly with calls like socket(...) & bind(..) call without using Qt ?

                  Have not tried yet, and probably will not have time for that soon.

                  Any reason you are calling bind(..) each time for each interfaces ?

                  Because I send a datagram on each interface and listen for answers.

                  You can also try simple with passing QHostAddress::AnyIPv4 with just one bind call.

                  Doesn't help. The first bind() call blocks, no matter which address is given. Even the overload that takes no parameters blocks.

                  Every next bind() is very fast. I think @Christian-Ehrlicher is right that it is some kind of network timeout. Not sure if DNS is involved here, but I will check more deeply when I installed Wireshark on that machine.

                  Qt has to stay free or it will die.

                  JonBJ 1 Reply Last reply
                  0
                  • dheerendraD Offline
                    dheerendraD Offline
                    dheerendra
                    Qt Champions 2022
                    wrote on last edited by
                    #15

                    Not sure if DNS is involved here,

                    DNS is not involved for bind. Only ARP can play role here. It is to get the MAC address corresponding to IP address. For the bind even this should not kick in. Even ARP will come into picture only if you start data transfer. Actually internally bind is not doing anything other than filling the Socket DataStructure with Source IP and Source Port#. If you are interested i can give you vanilla socket program to check on this.

                    Dheerendra
                    @Community Service
                    Certified Qt Specialist
                    http://www.pthinks.com

                    aha_1980A 1 Reply Last reply
                    0
                    • aha_1980A aha_1980

                      @dheerendra

                      How about checking directly with calls like socket(...) & bind(..) call without using Qt ?

                      Have not tried yet, and probably will not have time for that soon.

                      Any reason you are calling bind(..) each time for each interfaces ?

                      Because I send a datagram on each interface and listen for answers.

                      You can also try simple with passing QHostAddress::AnyIPv4 with just one bind call.

                      Doesn't help. The first bind() call blocks, no matter which address is given. Even the overload that takes no parameters blocks.

                      Every next bind() is very fast. I think @Christian-Ehrlicher is right that it is some kind of network timeout. Not sure if DNS is involved here, but I will check more deeply when I installed Wireshark on that machine.

                      JonBJ Online
                      JonBJ Online
                      JonB
                      wrote on last edited by
                      #16

                      @aha_1980
                      You state that the first bind() is what takes the extra time. However, your debug output prints start before it does anything and then does not print anything till after the first bind() has completed, and state that must be what is taking the time.

                      I think you should determine whether that time is actually during the QNetworkInterface::allAddresses() call, while it gathers all addresses. Pull that into its own variable and time just that part. Is that actually where the 3 seconds is spent?

                      aha_1980A 1 Reply Last reply
                      0
                      • JonBJ JonB

                        @aha_1980
                        You state that the first bind() is what takes the extra time. However, your debug output prints start before it does anything and then does not print anything till after the first bind() has completed, and state that must be what is taking the time.

                        I think you should determine whether that time is actually during the QNetworkInterface::allAddresses() call, while it gathers all addresses. Pull that into its own variable and time just that part. Is that actually where the 3 seconds is spent?

                        aha_1980A Offline
                        aha_1980A Offline
                        aha_1980
                        Lifetime Qt Champion
                        wrote on last edited by
                        #17

                        @JonB

                        Please read the topic title from the beginning :)

                        I think you should determine whether that time is actually during the QNetworkInterface::allAddresses() call, while it gathers all addresses. Pull that into its own variable and time just that part. Is that actually where the 3 seconds is spent?

                        I already expected that comment - but it's valid. No, it's really the bind() that takes the time. I already split that up to gather the addresses and bind each interface separate in a QTimers timeout, but it does not help.

                        Fact is, the first bind() takes ages and blocks the GUI.

                        Qt has to stay free or it will die.

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                        • dheerendraD dheerendra

                          Not sure if DNS is involved here,

                          DNS is not involved for bind. Only ARP can play role here. It is to get the MAC address corresponding to IP address. For the bind even this should not kick in. Even ARP will come into picture only if you start data transfer. Actually internally bind is not doing anything other than filling the Socket DataStructure with Source IP and Source Port#. If you are interested i can give you vanilla socket program to check on this.

                          aha_1980A Offline
                          aha_1980A Offline
                          aha_1980
                          Lifetime Qt Champion
                          wrote on last edited by
                          #18

                          @dheerendra Yes, I'd try a vanilla program if you got one.

                          I just will not get around to do this today, as I'm starting to Qt Summit in a few hours. So testing will have to wait at least until friday.

                          Qt has to stay free or it will die.

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                          • dheerendraD Offline
                            dheerendraD Offline
                            dheerendra
                            Qt Champions 2022
                            wrote on last edited by dheerendra
                            #19

                            Please share an email on the chat message. I will drop you an email with the program.

                            Dheerendra
                            @Community Service
                            Certified Qt Specialist
                            http://www.pthinks.com

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                            • aha_1980A Offline
                              aha_1980A Offline
                              aha_1980
                              Lifetime Qt Champion
                              wrote on last edited by
                              #20

                              Just as short interim report: A simple Windows winsock2 API program binds immediately. So it looks like I have to dig deeper, I just don't have the time for that right now. I'll come back to this problem later.

                              Thanks for all your help so far.

                              Qt has to stay free or it will die.

                              JonBJ 1 Reply Last reply
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                              • aha_1980A aha_1980

                                Just as short interim report: A simple Windows winsock2 API program binds immediately. So it looks like I have to dig deeper, I just don't have the time for that right now. I'll come back to this problem later.

                                Thanks for all your help so far.

                                JonBJ Online
                                JonBJ Online
                                JonB
                                wrote on last edited by JonB
                                #21

                                @aha_1980
                                Just as a short interim suggestion: As you are an expert Qt-er, if you're set up to run your program profiled would that immediately tell you where the extra time is being spent?

                                aha_1980A 1 Reply Last reply
                                0
                                • JonBJ JonB

                                  @aha_1980
                                  Just as a short interim suggestion: As you are an expert Qt-er, if you're set up to run your program profiled would that immediately tell you where the extra time is being spent?

                                  aha_1980A Offline
                                  aha_1980A Offline
                                  aha_1980
                                  Lifetime Qt Champion
                                  wrote on last edited by
                                  #22

                                  @JonB probably. But nevertheless I'd need to dig into Qt sources. Also, this problem is one Windows (I'm not even sure if it is machine specific), and I dont have a debug/profile Qt setup there.

                                  Otherwise I'd not asked ;)

                                  Qt has to stay free or it will die.

                                  L 1 Reply Last reply
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                                  • aha_1980A aha_1980

                                    @JonB probably. But nevertheless I'd need to dig into Qt sources. Also, this problem is one Windows (I'm not even sure if it is machine specific), and I dont have a debug/profile Qt setup there.

                                    Otherwise I'd not asked ;)

                                    L Offline
                                    L Offline
                                    Light Chaos
                                    wrote on last edited by
                                    #23

                                    @aha_1980 Try this: setProxy(QNetworkProxy::NoProxy)

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