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problem with System()

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  • J jsulm
    24 Jun 2016, 08:09

    /home is not the full path to your application except it is called home and is located in the root directory.
    So, you can start the program in a shell with /home/princi?
    Did you try it?
    This is quite strange path: in /home you usually have a directory for each user and /home is not writable by normal user.

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    AlvaroS
    wrote on 24 Jun 2016, 08:23 last edited by
    #15

    @jsulm sorry yes, it is in /home/user1/ but it does not run as well...

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      mrjj
      Lifetime Qt Champion
      wrote on 24 Jun 2016, 08:25 last edited by
      #16

      @AlvaroS said:

      QString program = "princi";

      should be

      QString program = "/home/user1/princi";

      ?

      A 1 Reply Last reply 24 Jun 2016, 08:28
      1
      • M mrjj
        24 Jun 2016, 08:25

        @AlvaroS said:

        QString program = "princi";

        should be

        QString program = "/home/user1/princi";

        ?

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        AlvaroS
        wrote on 24 Jun 2016, 08:28 last edited by
        #17

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

        J M 2 Replies Last reply 24 Jun 2016, 08:29
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        • A AlvaroS
          24 Jun 2016, 08:28

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

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          jsulm
          Lifetime Qt Champion
          wrote on 24 Jun 2016, 08:29 last edited by
          #18

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

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

          A 1 Reply Last reply 24 Jun 2016, 08:31
          1
          • A AlvaroS
            24 Jun 2016, 08:28

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

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            mrjj
            Lifetime Qt Champion
            wrote on 24 Jun 2016, 08:30 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.

            A 1 Reply Last reply 24 Jun 2016, 08:38
            2
            • J jsulm
              24 Jun 2016, 08:29

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

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              AlvaroS
              wrote on 24 Jun 2016, 08:31 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

              J A 2 Replies Last reply 24 Jun 2016, 08:33
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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

                J Offline
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                jsulm
                Lifetime Qt Champion
                wrote on 24 Jun 2016, 08:33 last edited by jsulm
                #21

                @AlvaroS Then try what @mrjj suggested

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

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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

                    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
                      1
                      • 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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                                  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

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