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problem with System()

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  • M mrjj
    24 Jun 2016, 08:30

    @AlvaroS

    Ok, you must debug then
    try to use
    http://doc.qt.io/qt-5/qprocess.html#error
    to see what it thinks.

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    AlvaroS
    wrote on 24 Jun 2016, 08:38 last edited by
    #22
    This post is deleted!
    M 1 Reply Last reply 24 Jun 2016, 08:40
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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

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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
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            • 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
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              • 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
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                • 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...

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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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