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problem with System()

Scheduled Pinned Locked Moved Unsolved General and Desktop
system commandsystem
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  • AlvaroSA AlvaroS

    @mrjj It works in the same way... :(

    mrjjM Offline
    mrjjM Offline
    mrjj
    Lifetime Qt Champion
    wrote on last edited by
    #19

    @AlvaroS

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

    AlvaroSA 1 Reply Last reply
    2
    • jsulmJ jsulm

      @AlvaroS So, if you enter /home/user1/princi in a terminal window and press enter it does not start? What happens? Any error message?

      AlvaroSA Offline
      AlvaroSA Offline
      AlvaroS
      wrote on last edited by
      #20

      @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

      jsulmJ AlvaroSA 2 Replies Last reply
      0
      • AlvaroSA AlvaroS

        @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

        jsulmJ Offline
        jsulmJ Offline
        jsulm
        Lifetime Qt Champion
        wrote on last edited by jsulm
        #21

        @AlvaroS Then try what @mrjj suggested

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

        1 Reply Last reply
        0
        • mrjjM mrjj

          @AlvaroS

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

          AlvaroSA Offline
          AlvaroSA Offline
          AlvaroS
          wrote on last edited by
          #22
          This post is deleted!
          mrjjM 1 Reply Last reply
          0
          • AlvaroSA AlvaroS

            @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

            AlvaroSA Offline
            AlvaroSA Offline
            AlvaroS
            wrote on 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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            • AlvaroSA AlvaroS

              This post is deleted!

              mrjjM Offline
              mrjjM Offline
              mrjj
              Lifetime Qt Champion
              wrote on 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

              AlvaroSA 1 Reply Last reply
              1
              • mrjjM mrjj

                @AlvaroS

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

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

                AlvaroSA Offline
                AlvaroSA Offline
                AlvaroS
                wrote on last edited by
                #25

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

                mrjjM 1 Reply Last reply
                0
                • AlvaroSA AlvaroS

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

                  mrjjM Offline
                  mrjjM Offline
                  mrjj
                  Lifetime Qt Champion
                  wrote on last edited by
                  #26

                  @AlvaroS

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

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

                  AlvaroSA 1 Reply Last reply
                  1
                  • mrjjM mrjj

                    @AlvaroS

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

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

                    AlvaroSA Offline
                    AlvaroSA Offline
                    AlvaroS
                    wrote on last edited by
                    #27

                    @mrjj Yes:

                        myProcess->start(program, arguments);
                    
                        QProcess::ProcessError error = myProcess->error();
                    
                    mrjjM 1 Reply Last reply
                    0
                    • AlvaroSA AlvaroS

                      @mrjj Yes:

                          myProcess->start(program, arguments);
                      
                          QProcess::ProcessError error = myProcess->error();
                      
                      mrjjM Offline
                      mrjjM Offline
                      mrjj
                      Lifetime Qt Champion
                      wrote on last edited by
                      #28

                      @AlvaroS
                      hmm really odd then
                      it should say FailedToStart

                      Just to be 100% clear.

                      princi is never run ?

                      AlvaroSA 1 Reply Last reply
                      1
                      • mrjjM mrjj

                        @AlvaroS
                        hmm really odd then
                        it should say FailedToStart

                        Just to be 100% clear.

                        princi is never run ?

                        AlvaroSA Offline
                        AlvaroSA Offline
                        AlvaroS
                        wrote on 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.

                        1 Reply Last reply
                        0
                        • mrjjM Offline
                          mrjjM Offline
                          mrjj
                          Lifetime Qt Champion
                          wrote on 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.

                          AlvaroSA 1 Reply Last reply
                          0
                          • mrjjM mrjj

                            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.

                            AlvaroSA Offline
                            AlvaroSA Offline
                            AlvaroS
                            wrote on 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" << "+" ;
                            
                            
                            1 Reply Last reply
                            0
                            • mrjjM Offline
                              mrjjM Offline
                              mrjj
                              Lifetime Qt Champion
                              wrote on 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 ?

                              AlvaroSA 2 Replies Last reply
                              0
                              • mrjjM mrjj

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

                                AlvaroSA Offline
                                AlvaroSA Offline
                                AlvaroS
                                wrote on last edited by
                                #33

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

                                1 Reply Last reply
                                0
                                • mrjjM mrjj

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

                                  AlvaroSA Offline
                                  AlvaroSA Offline
                                  AlvaroS
                                  wrote on 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...

                                  mrjjM 1 Reply Last reply
                                  0
                                  • SGaistS Offline
                                    SGaistS Offline
                                    SGaist
                                    Lifetime Qt Champion
                                    wrote on 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

                                    AlvaroSA 1 Reply Last reply
                                    1
                                    • SGaistS SGaist

                                      What is that + sign doing as parameter ?

                                      AlvaroSA Offline
                                      AlvaroSA Offline
                                      AlvaroS
                                      wrote on last edited by
                                      #36

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

                                      1 Reply Last reply
                                      0
                                      • AlvaroSA AlvaroS

                                        @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...

                                        mrjjM Offline
                                        mrjjM Offline
                                        mrjj
                                        Lifetime Qt Champion
                                        wrote on 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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