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problem with System()

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  • A AlvaroS
    24 Jun 2016, 08:31

    @jsulm In a terminal if I write

    ./princi 0 747.37 427.68 0 844.37 42.54 prueba_princi.bmp 0 0 +
    

    in /home/user1/ directory it runs good

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    AlvaroS
    wrote on 24 Jun 2016, 08:39 last edited by AlvaroS
    #23

    @AlvaroS said:

    @jsulm In a terminal if I write

    ./princi 0 747.37 427.68 0 844.37 42.54 prueba_princi.bmp 0 0 +
    

    in /home/user1/ directory it runs good

    @jsulm said:

    @AlvaroS Then try what @mrjj suggested

    okey, it gives me UnknowError.... http://doc.qt.io/qt-5/qprocess.html#ProcessError-enum

    1 Reply Last reply
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    • A AlvaroS
      24 Jun 2016, 08:38

      This post is deleted!

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      mrjj
      Lifetime Qt Champion
      wrote on 24 Jun 2016, 08:40 last edited by
      #24

      @AlvaroS

      well you can use
      qDebug() "qproc: " << myProcess->error();

      and check the code in
      http://doc.qt.io/qt-5/qprocess.html#ProcessError-enum

      A 1 Reply Last reply 24 Jun 2016, 08:42
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      • M mrjj
        24 Jun 2016, 08:40

        @AlvaroS

        well you can use
        qDebug() "qproc: " << myProcess->error();

        and check the code in
        http://doc.qt.io/qt-5/qprocess.html#ProcessError-enum

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        AlvaroS
        wrote on 24 Jun 2016, 08:42 last edited by
        #25

        @mrjj Yes thanks!! See my last post. Thanks again. It gives me Unknow error...

        M 1 Reply Last reply 24 Jun 2016, 08:43
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        • A AlvaroS
          24 Jun 2016, 08:42

          @mrjj Yes thanks!! See my last post. Thanks again. It gives me Unknow error...

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          mrjj
          Lifetime Qt Champion
          wrote on 24 Jun 2016, 08:43 last edited by
          #26

          @AlvaroS

          " This is the default return value of error()."

          You do call it AFTER u call
          myProcess->start(program,arguments); ?

          A 1 Reply Last reply 24 Jun 2016, 08:44
          1
          • M mrjj
            24 Jun 2016, 08:43

            @AlvaroS

            " This is the default return value of error()."

            You do call it AFTER u call
            myProcess->start(program,arguments); ?

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            AlvaroS
            wrote on 24 Jun 2016, 08:44 last edited by
            #27

            @mrjj Yes:

                myProcess->start(program, arguments);
            
                QProcess::ProcessError error = myProcess->error();
            
            M 1 Reply Last reply 24 Jun 2016, 08:46
            0
            • A AlvaroS
              24 Jun 2016, 08:44

              @mrjj Yes:

                  myProcess->start(program, arguments);
              
                  QProcess::ProcessError error = myProcess->error();
              
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              mrjj
              Lifetime Qt Champion
              wrote on 24 Jun 2016, 08:46 last edited by
              #28

              @AlvaroS
              hmm really odd then
              it should say FailedToStart

              Just to be 100% clear.

              princi is never run ?

              A 1 Reply Last reply 24 Jun 2016, 08:48
              1
              • M mrjj
                24 Jun 2016, 08:46

                @AlvaroS
                hmm really odd then
                it should say FailedToStart

                Just to be 100% clear.

                princi is never run ?

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                AlvaroS
                wrote on 24 Jun 2016, 08:48 last edited by
                #29

                @mrjj said:

                @AlvaroS
                hmm really odd then
                it should say FailedToStart

                Just to be 100% clear.

                princi is never run ?

                okey look.
                if I write:

                    myProcess->start(program, arguments);
                
                    myProcess->waitForFinished(3000);
                
                    QProcess::ProcessError error = myProcess->error();
                
                

                Now error says:
                QProcess::Crashed The process crashed some time after starting successfully.

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                • M Offline
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                  mrjj
                  Lifetime Qt Champion
                  wrote on 24 Jun 2016, 08:49 last edited by mrjj
                  #30

                  so it sounds like your princi do run but it crashes?

                  oh. sorry my bad. start is async so calling error right after was
                  not correct.

                  waitForFinished fixed that.

                  A 1 Reply Last reply 24 Jun 2016, 08:54
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                  • M mrjj
                    24 Jun 2016, 08:49

                    so it sounds like your princi do run but it crashes?

                    oh. sorry my bad. start is async so calling error right after was
                    not correct.

                    waitForFinished fixed that.

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                    AlvaroS
                    wrote on 24 Jun 2016, 08:54 last edited by
                    #31

                    @mrjj Yes... I think so...
                    How should I pass the arguments?

                    the arguments of princi are:

                    0 wps.front().x() wps.front().y() 0 wps.back().x() wps.front().y() prueba_princi.bmp 0 0 +
                    

                    so my QStringList arguments is:

                     QStringList arguments;
                    arguments << "0" << QString::number(wps.front().x()) << QString::number(wps.front().y()) << "0" << QString::number(wps.back().x()) << QString::number(wps.back().y()) << "prueba_princi.bmp" << "0" << "0" << "+" ;
                    
                    
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                    • M Offline
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                      mrjj
                      Lifetime Qt Champion
                      wrote on 24 Jun 2016, 09:11 last edited by
                      #32

                      it seems fine
                      You should look inside princi for how it
                      reads it. it must be that part that is crashing ?

                      A 2 Replies Last reply 24 Jun 2016, 09:22
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                      • M mrjj
                        24 Jun 2016, 09:11

                        it seems fine
                        You should look inside princi for how it
                        reads it. it must be that part that is crashing ?

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                        AlvaroS
                        wrote on 24 Jun 2016, 09:22 last edited by
                        #33

                        @mrjj yes, but it really rare that if I run from terminal princi runs good...

                        1 Reply Last reply
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                        • M mrjj
                          24 Jun 2016, 09:11

                          it seems fine
                          You should look inside princi for how it
                          reads it. it must be that part that is crashing ?

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                          AlvaroS
                          wrote on 24 Jun 2016, 09:31 last edited by AlvaroS
                          #34

                          @mrjj And if I write:

                          system ("./princi 0 5 10 0 7 8 prueba_princi.bmp 0 0 +")
                          where 5,10,7 and 8 are wps.front,wps.back....
                          it runs well...

                          M 1 Reply Last reply 24 Jun 2016, 09:43
                          0
                          • S Offline
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                            SGaist
                            Lifetime Qt Champion
                            wrote on 24 Jun 2016, 09:32 last edited by
                            #35

                            What is that + sign doing as parameter ?

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

                            A 1 Reply Last reply 24 Jun 2016, 09:32
                            1
                            • S SGaist
                              24 Jun 2016, 09:32

                              What is that + sign doing as parameter ?

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                              AlvaroS
                              wrote on 24 Jun 2016, 09:32 last edited by
                              #36

                              @SGaist + is just and argument that i have to pass to princi

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                              • A AlvaroS
                                24 Jun 2016, 09:31

                                @mrjj And if I write:

                                system ("./princi 0 5 10 0 7 8 prueba_princi.bmp 0 0 +")
                                where 5,10,7 and 8 are wps.front,wps.back....
                                it runs well...

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                                mrjj
                                Lifetime Qt Champion
                                wrote on 24 Jun 2016, 09:43 last edited by
                                #37

                                @AlvaroS
                                well you must debug it then.
                                Try to qDebug inside princi what you read and compare that to what u read for
                                system ("./princi 0 5 10 0 7 8 prueba_princi.bmp 0 0 +")

                                Sadly We cannot guess why you crash from the code shown.

                                Also you dump the arguments to qDebug before u
                                call start, just to see what u are sending also.

                                and then take it from there.

                                1 Reply Last reply
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