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Executing QProcess in QThread: memory leak

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  • KroMignonK KroMignon

    @sitesv said in Executing QProcess in QThread: memory leak:

    How to set a timeout for the process execution in this case?

    Have you tried to look at ping parameters (ping --help)

    And I would only wait once, for all pings to be done:

    QStringList ip_list = {"192.168.0.1", "192.168.0.2"};
    int success_count = 0;
    int pingsToDo = ip_list.count();
    QEventLoop l;
    foreach(auto ip, ip_list)
    {
        QProcess ping;
        ping.setProcessChannelMode(QProcess::MergedChannels);
        connect(&ping,
                QOverload<int, QProcess::ExitStatus>::of(&QProcess::finished),
                [&l, &ping, &success_count, &pingsToDo]() {
                    --pingsToDo;
                    QString output(ping.readAll());
                    if(output.contains("ttl",Qt::CaseInsensitive)) success_count++;
                    if(!pingsToDo)
                        l.exit();
                });
        ping.start("/bin/ping", QStringList() << ip << "-c" << "1");
    }
    
    // wait all pings done
    l.exec();
    if(success_count == ip_list.count())
       emit setStatus(true);
    else
       emit setStatus(false);
    m_timer->start();
    
    sitesvS Offline
    sitesvS Offline
    sitesv
    wrote on last edited by sitesv
    #55

    @KroMignon said in Executing QProcess in QThread: memory leak:

    And I would only wait once, for all pings to be done:

    Wow! Very nice!! Thank you!

    @KroMignon
    UPD: app is freezing on line l.exec() althought l.exit() is done....

    1 Reply Last reply
    0
    • sitesvS Offline
      sitesvS Offline
      sitesv
      wrote on last edited by
      #56

      Guys, how to resolve this?

      KroMignonK 1 Reply Last reply
      0
      • sitesvS sitesv

        Guys, how to resolve this?

        KroMignonK Offline
        KroMignonK Offline
        KroMignon
        wrote on last edited by
        #57

        @sitesv said in Executing QProcess in QThread: memory leak:

        Guys, how to resolve this?

        Hmm, I think it is a tricky issue. I would start with forcing QueuedConnection, to avoid threading issues:

        connect(&ping,
                    QOverload<int, QProcess::ExitStatus>::of(&QProcess::finished),
                    [&l, &ping, &success_count, &pingsToDo]() {
                        ...
                    }, Qt::QueuedConnection);
        

        It is an old maxim of mine that when you have excluded the impossible, whatever remains, however improbable, must be the truth. (Sherlock Holmes)

        sitesvS 1 Reply Last reply
        0
        • KroMignonK KroMignon

          @sitesv said in Executing QProcess in QThread: memory leak:

          Guys, how to resolve this?

          Hmm, I think it is a tricky issue. I would start with forcing QueuedConnection, to avoid threading issues:

          connect(&ping,
                      QOverload<int, QProcess::ExitStatus>::of(&QProcess::finished),
                      [&l, &ping, &success_count, &pingsToDo]() {
                          ...
                      }, Qt::QueuedConnection);
          
          sitesvS Offline
          sitesvS Offline
          sitesv
          wrote on last edited by
          #58

          @KroMignon said in Executing QProcess in QThread: memory leak:

          connect(&ping,
          QOverload<int, QProcess::ExitStatus>::of(&QProcess::finished),
          &l, &ping, &success_count, &pingsToDo {
          ...
          }, Qt::QueuedConnection);

          'connect' failed again
          img1.png

          KroMignonK 2 Replies Last reply
          0
          • sitesvS sitesv

            @KroMignon said in Executing QProcess in QThread: memory leak:

            connect(&ping,
            QOverload<int, QProcess::ExitStatus>::of(&QProcess::finished),
            &l, &ping, &success_count, &pingsToDo {
            ...
            }, Qt::QueuedConnection);

            'connect' failed again
            img1.png

            KroMignonK Offline
            KroMignonK Offline
            KroMignon
            wrote on last edited by KroMignon
            #59

            @sitesv Can you show the code you have written

            Sorry my fault, should be:

            connect(&ping,
                    QOverload<int, QProcess::ExitStatus>::of(&QProcess::finished),
                    &l, // receiver!
                    [&l, &ping, &success_count, &pingsToDo]() {
                        ...
                    }, Qt::QueuedConnection);
            

            It is an old maxim of mine that when you have excluded the impossible, whatever remains, however improbable, must be the truth. (Sherlock Holmes)

            sitesvS 1 Reply Last reply
            0
            • KroMignonK KroMignon

              @sitesv Can you show the code you have written

              Sorry my fault, should be:

              connect(&ping,
                      QOverload<int, QProcess::ExitStatus>::of(&QProcess::finished),
                      &l, // receiver!
                      [&l, &ping, &success_count, &pingsToDo]() {
                          ...
                      }, Qt::QueuedConnection);
              
              sitesvS Offline
              sitesvS Offline
              sitesv
              wrote on last edited by
              #60

              @KroMignon

              QStringList ip_list = {"192.168.0.1", "192.168.0.2"};
                  int success_count = 0;
                  int pingsToDo = ip_list.count();
                  QEventLoop l; // used for passive wait until process finished
                  foreach(auto ip, ip_list)
                  {
                      QProcess ping;
                      ping.setProcessChannelMode(QProcess::MergedChannels);
                      connect(&ping,
                              QOverload<int, QProcess::ExitStatus>::of(&QProcess::finished), &l,
                              [&l, &ping, &success_count, &pingsToDo]() {
                                  --pingsToDo;
                                  QString output(ping.readAll()); // <<<<<<<<<<<<<<<< SIGSEGV Segmentation fault
                                  if(output.contains("ttl",Qt::CaseInsensitive)){
                                      success_count++;
                                  }
                                  if(!pingsToDo){
                                      l.exit();
                                  }
                              }, Qt::QueuedConnection);
                      ping.start("/bin/ping", QStringList() << ip << "-c" << "1");
                  }
                  l.exec();
                  if(success_count == ip_list.count()) emit setLedStatus(0, 0, true);
                  else                                 emit setLedStatus(0, 0, false);
              
                  m_timer->start();
              
              

              There is SIGSEGV Segmentation fault on ping.readAll string. :((

              1 Reply Last reply
              0
              • sitesvS sitesv

                @KroMignon said in Executing QProcess in QThread: memory leak:

                connect(&ping,
                QOverload<int, QProcess::ExitStatus>::of(&QProcess::finished),
                &l, &ping, &success_count, &pingsToDo {
                ...
                }, Qt::QueuedConnection);

                'connect' failed again
                img1.png

                KroMignonK Offline
                KroMignonK Offline
                KroMignon
                wrote on last edited by KroMignon
                #61

                @sitesv Sorry but I was a little bit confused when I suggest you this code.
                This cannot work, because QProcess is killed/destroyed at end of the for loop!
                Should be:

                QStringList ip_list = {"192.168.0.1", "192.168.0.2"};
                int success_count = 0;
                int pingsToDo = ip_list.count();
                QEventLoop l;
                foreach(auto ip, ip_list)
                {
                    auto ping = new QProcess();
                    ping->setProcessChannelMode(QProcess::MergedChannels);
                    connect(ping,
                            QOverload<int, QProcess::ExitStatus>::of(&QProcess::finished),
                            [&l, ping, &success_count, &pingsToDo]() {
                                --pingsToDo;
                                QString output(ping->readAll());
                                if(output.contains("ttl",Qt::CaseInsensitive))
                                    success_count++;
                                // free memory
                                ping->deleteLater();
                                //  exit event loop after all pings done
                                if(!pingsToDo)
                                    l.exit();
                            });
                    ping->start("/bin/ping", QStringList() << ip << "-c" << "1");
                }
                
                // wait all pings done
                l.exec();
                

                It is an old maxim of mine that when you have excluded the impossible, whatever remains, however improbable, must be the truth. (Sherlock Holmes)

                1 Reply Last reply
                0
                • JonBJ Offline
                  JonBJ Offline
                  JonB
                  wrote on last edited by
                  #62

                  @sitesv , @KroMignon
                  I will say one thing.

                  You are writing code which will call QEventLoop::exec(), blocking whatever calls it. It relies on hitting the QEventLoop::exit() statement, which you only have in response to the QProcess::finished signal. If for whatever reason that does not get hit, your event loop will never be exited.

                  I would not write production (or even development) code like this, and certainly not for distribution. It is asking for an "unseen hang" to occur, one day. I would at minimum hook onto QProcess::errorOccurred, maybe stateChanged() too. And I would put in some sort of timer/timeout, so that if something goes badly wrong you get out of the blocking loop (with perhaps an error flag) instead of waiting for Hell to freeze over....

                  KroMignonK 1 Reply Last reply
                  3
                  • JonBJ JonB

                    @sitesv , @KroMignon
                    I will say one thing.

                    You are writing code which will call QEventLoop::exec(), blocking whatever calls it. It relies on hitting the QEventLoop::exit() statement, which you only have in response to the QProcess::finished signal. If for whatever reason that does not get hit, your event loop will never be exited.

                    I would not write production (or even development) code like this, and certainly not for distribution. It is asking for an "unseen hang" to occur, one day. I would at minimum hook onto QProcess::errorOccurred, maybe stateChanged() too. And I would put in some sort of timer/timeout, so that if something goes badly wrong you get out of the blocking loop (with perhaps an error flag) instead of waiting for Hell to freeze over....

                    KroMignonK Offline
                    KroMignonK Offline
                    KroMignon
                    wrote on last edited by
                    #63

                    @JonB said in Executing QProcess in QThread: memory leak:

                    I would not write production (or even development) code like this, and certainly not for distribution. It is asking for an "unseen hang" to occur, one day. I would at minimum hook onto QProcess::errorOccurred, maybe stateChanged() too. And I would put in some sort of timer/timeout, so that if something goes badly wrong you get out of the blocking loop (with perhaps an error flag) instead of waiting for Hell to freeze over....

                    Yes, this is a good advice.

                    It is an old maxim of mine that when you have excluded the impossible, whatever remains, however improbable, must be the truth. (Sherlock Holmes)

                    sitesvS 1 Reply Last reply
                    1
                    • KroMignonK KroMignon

                      @JonB said in Executing QProcess in QThread: memory leak:

                      I would not write production (or even development) code like this, and certainly not for distribution. It is asking for an "unseen hang" to occur, one day. I would at minimum hook onto QProcess::errorOccurred, maybe stateChanged() too. And I would put in some sort of timer/timeout, so that if something goes badly wrong you get out of the blocking loop (with perhaps an error flag) instead of waiting for Hell to freeze over....

                      Yes, this is a good advice.

                      sitesvS Offline
                      sitesvS Offline
                      sitesv
                      wrote on last edited by sitesv
                      #64

                      @JonB said in Executing QProcess in QThread: memory leak:

                      You are writing code which will call QEventLoop::exec(), blocking whatever calls it. It relies on hitting the QEventLoop::exit() statement, which you only have in response to the QProcess::finished signal. If for whatever reason that does not get hit, your event loop will never be exited.

                      Maybe my first variant was good (QThread + QProcess)?

                      if(!myProcess) myProcess = new QProcess(this);
                      myProcess->start(exe_path, arguments);
                      myProcess->waitForFinished(500);
                      output = myProcess->readAll();
                      output_str = codec->toUnicode(output);
                      output_strlst = output_str.split("\r\n");
                      myProcess->close();
                      ...
                      

                      There is QProcess "waitForFinished" with timeout.
                      The app wasn't freezing with this approach.

                      KroMignonK jsulmJ 2 Replies Last reply
                      0
                      • sitesvS sitesv

                        @JonB said in Executing QProcess in QThread: memory leak:

                        You are writing code which will call QEventLoop::exec(), blocking whatever calls it. It relies on hitting the QEventLoop::exit() statement, which you only have in response to the QProcess::finished signal. If for whatever reason that does not get hit, your event loop will never be exited.

                        Maybe my first variant was good (QThread + QProcess)?

                        if(!myProcess) myProcess = new QProcess(this);
                        myProcess->start(exe_path, arguments);
                        myProcess->waitForFinished(500);
                        output = myProcess->readAll();
                        output_str = codec->toUnicode(output);
                        output_strlst = output_str.split("\r\n");
                        myProcess->close();
                        ...
                        

                        There is QProcess "waitForFinished" with timeout.
                        The app wasn't freezing with this approach.

                        KroMignonK Offline
                        KroMignonK Offline
                        KroMignon
                        wrote on last edited by
                        #65

                        @sitesv said in Executing QProcess in QThread: memory leak:

                        There is QProcess "waitForFinished" with timeout.
                        The app wasn't freezing with this approach.

                        Why not, but you have to wait ping finished before starting next.
                        If it is what you want, then go with it.

                        It is an old maxim of mine that when you have excluded the impossible, whatever remains, however improbable, must be the truth. (Sherlock Holmes)

                        1 Reply Last reply
                        0
                        • sitesvS sitesv

                          @JonB said in Executing QProcess in QThread: memory leak:

                          You are writing code which will call QEventLoop::exec(), blocking whatever calls it. It relies on hitting the QEventLoop::exit() statement, which you only have in response to the QProcess::finished signal. If for whatever reason that does not get hit, your event loop will never be exited.

                          Maybe my first variant was good (QThread + QProcess)?

                          if(!myProcess) myProcess = new QProcess(this);
                          myProcess->start(exe_path, arguments);
                          myProcess->waitForFinished(500);
                          output = myProcess->readAll();
                          output_str = codec->toUnicode(output);
                          output_strlst = output_str.split("\r\n");
                          myProcess->close();
                          ...
                          

                          There is QProcess "waitForFinished" with timeout.
                          The app wasn't freezing with this approach.

                          jsulmJ Offline
                          jsulmJ Offline
                          jsulm
                          Lifetime Qt Champion
                          wrote on last edited by
                          #66

                          @sitesv I'm still wondering why you think you need a local event loop...

                          https://forum.qt.io/topic/113070/qt-code-of-conduct

                          sitesvS 1 Reply Last reply
                          1
                          • jsulmJ jsulm

                            @sitesv I'm still wondering why you think you need a local event loop...

                            sitesvS Offline
                            sitesvS Offline
                            sitesv
                            wrote on last edited by
                            #67

                            @jsulm said in Executing QProcess in QThread: memory leak:

                            @sitesv I'm still wondering why you think you need a local event loop...

                            Hi! I have done variant as you recommend. It's working!

                            void PingTester::doPing(){
                                QStringList ip_list = {"192.168.0.1", "192.168.0.2"};
                                int success_count = 0;
                                int pingsToDo = ip_list.count();
                                int ipCnt = pingsToDo;
                                foreach(auto ip, ip_list)
                                {
                                    QProcess ping;
                                    ping.setProcessChannelMode(QProcess::MergedChannels);
                                    connect(&ping,
                                            QOverload<int, QProcess::ExitStatus>::of(&QProcess::finished),
                                            [this, &ping, &success_count, &pingsToDo, ipCnt]() {
                                                --pingsToDo;
                                                QString output(ping.readAll());
                                                if(output.contains("ttl",Qt::CaseInsensitive)){
                                                    success_count++;
                                                }
                                                if(!pingsToDo){
                                                    if(success_count == ipCnt) emit setStatus(true);
                                                    else                       emit setStatus(false);
                                                    m_timer->start();
                                                }
                                            });
                                    ping.start("/bin/ping", QStringList() << ip << "-c" << "1" << "-w" << "1");
                                }
                            }
                            

                            I made another experiment:

                            1. Created a QThread
                            2. In QThread::run() method::
                            • made a QTimer* object,
                            • set him as "one shot kind",
                            • ran QTimer, and in final
                              * ran QThread::exec() (for run local EventLoop)...
                            1. There is timer->start() in timeout slot, It executed, but QTimer doesn't start again.

                            Any ideas?

                            JonBJ KroMignonK 2 Replies Last reply
                            0
                            • sitesvS sitesv

                              @jsulm said in Executing QProcess in QThread: memory leak:

                              @sitesv I'm still wondering why you think you need a local event loop...

                              Hi! I have done variant as you recommend. It's working!

                              void PingTester::doPing(){
                                  QStringList ip_list = {"192.168.0.1", "192.168.0.2"};
                                  int success_count = 0;
                                  int pingsToDo = ip_list.count();
                                  int ipCnt = pingsToDo;
                                  foreach(auto ip, ip_list)
                                  {
                                      QProcess ping;
                                      ping.setProcessChannelMode(QProcess::MergedChannels);
                                      connect(&ping,
                                              QOverload<int, QProcess::ExitStatus>::of(&QProcess::finished),
                                              [this, &ping, &success_count, &pingsToDo, ipCnt]() {
                                                  --pingsToDo;
                                                  QString output(ping.readAll());
                                                  if(output.contains("ttl",Qt::CaseInsensitive)){
                                                      success_count++;
                                                  }
                                                  if(!pingsToDo){
                                                      if(success_count == ipCnt) emit setStatus(true);
                                                      else                       emit setStatus(false);
                                                      m_timer->start();
                                                  }
                                              });
                                      ping.start("/bin/ping", QStringList() << ip << "-c" << "1" << "-w" << "1");
                                  }
                              }
                              

                              I made another experiment:

                              1. Created a QThread
                              2. In QThread::run() method::
                              • made a QTimer* object,
                              • set him as "one shot kind",
                              • ran QTimer, and in final
                                * ran QThread::exec() (for run local EventLoop)...
                              1. There is timer->start() in timeout slot, It executed, but QTimer doesn't start again.

                              Any ideas?

                              JonBJ Offline
                              JonBJ Offline
                              JonB
                              wrote on last edited by JonB
                              #68

                              @sitesv
                              I don't know how/whether your issue relates this, but in your code: you set off ping.start(), but QProcess ping; is a local variable in your foreach loop and so immediately goes out of scope (not to mention, you also re-use the same local variable for each time round the loop, overwriting/destroying the previous one). Nothing should work (it might actually "crash"), I don't understand how you say it does.

                              On top of all of this: I think we've said it already here above, but goodness only knows why you are using a thread, with all the complications that involves? If you want to run a QProcess and the main thread to know when it's finished, it's asynchronous anyway, it would be a whole lot simpler not to have any thread. I think I said this earlier, but up to you.

                              And finally, while I'm on a roll: I think you are just using a /bin/ping in order to read the textual output, parse it, and see whether something is there/alive. In which case I'd be tempted to just write it myself in Qt instead of running some external command, I would have thought it's only a few lines of code. Your "parsing" of the output is beyond hokey, not even sure what you think it tells you....

                              1 Reply Last reply
                              0
                              • sitesvS sitesv

                                @jsulm said in Executing QProcess in QThread: memory leak:

                                @sitesv I'm still wondering why you think you need a local event loop...

                                Hi! I have done variant as you recommend. It's working!

                                void PingTester::doPing(){
                                    QStringList ip_list = {"192.168.0.1", "192.168.0.2"};
                                    int success_count = 0;
                                    int pingsToDo = ip_list.count();
                                    int ipCnt = pingsToDo;
                                    foreach(auto ip, ip_list)
                                    {
                                        QProcess ping;
                                        ping.setProcessChannelMode(QProcess::MergedChannels);
                                        connect(&ping,
                                                QOverload<int, QProcess::ExitStatus>::of(&QProcess::finished),
                                                [this, &ping, &success_count, &pingsToDo, ipCnt]() {
                                                    --pingsToDo;
                                                    QString output(ping.readAll());
                                                    if(output.contains("ttl",Qt::CaseInsensitive)){
                                                        success_count++;
                                                    }
                                                    if(!pingsToDo){
                                                        if(success_count == ipCnt) emit setStatus(true);
                                                        else                       emit setStatus(false);
                                                        m_timer->start();
                                                    }
                                                });
                                        ping.start("/bin/ping", QStringList() << ip << "-c" << "1" << "-w" << "1");
                                    }
                                }
                                

                                I made another experiment:

                                1. Created a QThread
                                2. In QThread::run() method::
                                • made a QTimer* object,
                                • set him as "one shot kind",
                                • ran QTimer, and in final
                                  * ran QThread::exec() (for run local EventLoop)...
                                1. There is timer->start() in timeout slot, It executed, but QTimer doesn't start again.

                                Any ideas?

                                KroMignonK Offline
                                KroMignonK Offline
                                KroMignon
                                wrote on last edited by
                                #69

                                @sitesv said in Executing QProcess in QThread: memory leak:

                                Hi! I have done variant as you recommend. It's working!

                                I am not sure this is really working!
                                I think you have to (re)learn C++ object life cycle.
                                You create a QProcess local instance in the for loop, this object will be destroyed at loop end.

                                It is an old maxim of mine that when you have excluded the impossible, whatever remains, however improbable, must be the truth. (Sherlock Holmes)

                                1 Reply Last reply
                                1
                                • sitesvS Offline
                                  sitesvS Offline
                                  sitesv
                                  wrote on last edited by sitesv
                                  #70

                                  @JonB @KroMignon
                                  Agree with you, guys.
                                  But it works...
                                  I can reimplement to QProcess pointers of PingTester class...

                                  KroMignonK 1 Reply Last reply
                                  0
                                  • sitesvS sitesv

                                    @JonB @KroMignon
                                    Agree with you, guys.
                                    But it works...
                                    I can reimplement to QProcess pointers of PingTester class...

                                    KroMignonK Offline
                                    KroMignonK Offline
                                    KroMignon
                                    wrote on last edited by
                                    #71

                                    @sitesv said in Executing QProcess in QThread: memory leak:

                                    But it works...

                                    It don't, "it seems to work" would be the correct answer ;)

                                    If you try to ping a not valid/accessible IP address, I am pretty sure it will not work.

                                    If you want to do it sequentially, you have to be consistent in your choice:

                                    foreach(auto ip, ip_list)
                                    {
                                        QProcess ping;
                                        ping.setProcessChannelMode(QProcess::MergedChannels);
                                        ping.start("/bin/ping", QStringList() << ip << "-c" << "1" << "-w" << "1");
                                        ping.waitForFinished(5000); // wait up to 5 seconds
                                        QString output(ping.readAll());
                                        if(output.contains("ttl",Qt::CaseInsensitive)){
                                            success_count++;
                                        }
                                    }
                                    

                                    It is an old maxim of mine that when you have excluded the impossible, whatever remains, however improbable, must be the truth. (Sherlock Holmes)

                                    sitesvS JonBJ 2 Replies Last reply
                                    0
                                    • KroMignonK KroMignon

                                      @sitesv said in Executing QProcess in QThread: memory leak:

                                      But it works...

                                      It don't, "it seems to work" would be the correct answer ;)

                                      If you try to ping a not valid/accessible IP address, I am pretty sure it will not work.

                                      If you want to do it sequentially, you have to be consistent in your choice:

                                      foreach(auto ip, ip_list)
                                      {
                                          QProcess ping;
                                          ping.setProcessChannelMode(QProcess::MergedChannels);
                                          ping.start("/bin/ping", QStringList() << ip << "-c" << "1" << "-w" << "1");
                                          ping.waitForFinished(5000); // wait up to 5 seconds
                                          QString output(ping.readAll());
                                          if(output.contains("ttl",Qt::CaseInsensitive)){
                                              success_count++;
                                          }
                                      }
                                      
                                      sitesvS Offline
                                      sitesvS Offline
                                      sitesv
                                      wrote on last edited by
                                      #72

                                      @KroMignon said in Executing QProcess in QThread: memory leak:

                                      If you try to ping a not valid/accessible IP address, I am pretty sure it will not work.

                                      There is "-w 1" key. It helps with unaccessible IP.

                                      KroMignonK 1 Reply Last reply
                                      0
                                      • KroMignonK KroMignon

                                        @sitesv said in Executing QProcess in QThread: memory leak:

                                        But it works...

                                        It don't, "it seems to work" would be the correct answer ;)

                                        If you try to ping a not valid/accessible IP address, I am pretty sure it will not work.

                                        If you want to do it sequentially, you have to be consistent in your choice:

                                        foreach(auto ip, ip_list)
                                        {
                                            QProcess ping;
                                            ping.setProcessChannelMode(QProcess::MergedChannels);
                                            ping.start("/bin/ping", QStringList() << ip << "-c" << "1" << "-w" << "1");
                                            ping.waitForFinished(5000); // wait up to 5 seconds
                                            QString output(ping.readAll());
                                            if(output.contains("ttl",Qt::CaseInsensitive)){
                                                success_count++;
                                            }
                                        }
                                        
                                        JonBJ Offline
                                        JonBJ Offline
                                        JonB
                                        wrote on last edited by JonB
                                        #73

                                        @KroMignon
                                        I would think doing it sequentially, with waitForFinished(), for his multiple IP addresses would be a poor way to do things. He has a number of IP addresses to check, these should be done in parallel....

                                        1 Reply Last reply
                                        0
                                        • sitesvS sitesv

                                          @KroMignon said in Executing QProcess in QThread: memory leak:

                                          If you try to ping a not valid/accessible IP address, I am pretty sure it will not work.

                                          There is "-w 1" key. It helps with unaccessible IP.

                                          KroMignonK Offline
                                          KroMignonK Offline
                                          KroMignon
                                          wrote on last edited by
                                          #74

                                          @sitesv said in Executing QProcess in QThread: memory leak:

                                          There is "-w 1" key. It helps with unaccessible IP.

                                          AFAIK "-w 1" will wait up to 1 second.
                                          I am sure you will got QProcess warnings about killing a process which is still running.

                                          It is an old maxim of mine that when you have excluded the impossible, whatever remains, however improbable, must be the truth. (Sherlock Holmes)

                                          sitesvS 1 Reply Last reply
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