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How to make QFile read the whole line

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  • ManiRonM ManiRon

    @VRonin but thsi doest read the full data

    jsulmJ Offline
    jsulmJ Offline
    jsulm
    Lifetime Qt Champion
    wrote on last edited by
    #20

    @ManiRon said in How to make QFile read the whole line:

    but thsi doest read the full data

    What is the output of

    qDebug() << actualRead << size_of_file;
    

    ?

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

    ManiRonM 1 Reply Last reply
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    • jsulmJ jsulm

      @ManiRon said in How to make QFile read the whole line:

      but thsi doest read the full data

      What is the output of

      qDebug() << actualRead << size_of_file;
      

      ?

      ManiRonM Offline
      ManiRonM Offline
      ManiRon
      wrote on last edited by ManiRon
      #21

      @jsulm said in How to make QFile read the whole line:

      size_of_file

      Size = 194 .

      I thought it was qdebug problem so i wrote the data read from the file to another file then also it remains the same as the data shown in the debug

      ManiRonM 1 Reply Last reply
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      • VRoninV Offline
        VRoninV Offline
        VRonin
        wrote on last edited by
        #22

        What is the value of actualRead?

        "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
        ~Napoleon Bonaparte

        On a crusade to banish setIndexWidget() from the holy land of Qt

        ManiRonM 1 Reply Last reply
        1
        • VRoninV VRonin

          What is the value of actualRead?

          ManiRonM Offline
          ManiRonM Offline
          ManiRon
          wrote on last edited by
          #23

          @VRonin

          Size = 194

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          0
          • VRoninV Offline
            VRoninV Offline
            VRonin
            wrote on last edited by
            #24

            That means the read doesn't actually stop with the null

            "La mort n'est rien, mais vivre vaincu et sans gloire, c'est mourir tous les jours"
            ~Napoleon Bonaparte

            On a crusade to banish setIndexWidget() from the holy land of Qt

            ManiRonM 1 Reply Last reply
            1
            • ManiRonM ManiRon

              @jsulm said in How to make QFile read the whole line:

              size_of_file

              Size = 194 .

              I thought it was qdebug problem so i wrote the data read from the file to another file then also it remains the same as the data shown in the debug

              ManiRonM Offline
              ManiRonM Offline
              ManiRon
              wrote on last edited by
              #25
              This post is deleted!
              1 Reply Last reply
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              • VRoninV VRonin

                That means the read doesn't actually stop with the null

                ManiRonM Offline
                ManiRonM Offline
                ManiRon
                wrote on last edited by ManiRon
                #26

                @VRonin

                Yes you are right sir, So what can we do ?

                JonBJ 1 Reply Last reply
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                • ManiRonM ManiRon

                  @VRonin

                  Yes you are right sir, So what can we do ?

                  JonBJ Offline
                  JonBJ Offline
                  JonB
                  wrote on last edited by JonB
                  #27

                  @ManiRon
                  "What can we do" about what? You've spent the whole time claiming the read stops at the NUL, now you confirm it does not, so what's the problem?

                  ManiRonM 2 Replies Last reply
                  1
                  • JonBJ JonB

                    @ManiRon
                    "What can we do" about what? You've spent the whole time claiming the read stops at the NUL, now you confirm it does not, so what's the problem?

                    ManiRonM Offline
                    ManiRonM Offline
                    ManiRon
                    wrote on last edited by
                    #28

                    @JonB

                    I am storing the data in QBytearray will that be a problem?

                    1 Reply Last reply
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                    • JonBJ JonB

                      @ManiRon
                      "What can we do" about what? You've spent the whole time claiming the read stops at the NUL, now you confirm it does not, so what's the problem?

                      ManiRonM Offline
                      ManiRonM Offline
                      ManiRon
                      wrote on last edited by
                      #29

                      @JonB

                      the size it specifies is correct but the data displayed is till the NUL

                      JonBJ 1 Reply Last reply
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                      • ManiRonM ManiRon

                        @JonB

                        the size it specifies is correct but the data displayed is till the NUL

                        JonBJ Offline
                        JonBJ Offline
                        JonB
                        wrote on last edited by
                        #30

                        @ManiRon said in How to make QFile read the whole line:

                        @JonB

                        the size it specifies is correct but the data displayed is till the NUL

                        But I said that was just how qDebug() displays data. Read up about how qDebug() displays strings/bytes, which may contain NUL.

                        ManiRonM 1 Reply Last reply
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                        • JonBJ JonB

                          @ManiRon said in How to make QFile read the whole line:

                          @JonB

                          the size it specifies is correct but the data displayed is till the NUL

                          But I said that was just how qDebug() displays data. Read up about how qDebug() displays strings/bytes, which may contain NUL.

                          ManiRonM Offline
                          ManiRonM Offline
                          ManiRon
                          wrote on last edited by
                          #31

                          @JonB

                          I have doubt in storing the data i store the data read in QBytearray

                          JonBJ 1 Reply Last reply
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                          • ManiRonM ManiRon

                            @JonB

                            I have doubt in storing the data i store the data read in QBytearray

                            JonBJ Offline
                            JonBJ Offline
                            JonB
                            wrote on last edited by
                            #32

                            @ManiRon
                            So read up how qDebug() displays a QByteArray (as well as a QString)!!
                            Something even as old as https://www.qtcentre.org/threads/54236-qDebug-donsn-t-display-0x00?p=243053#post243053 will presumably do you.....

                            ManiRonM 1 Reply Last reply
                            2
                            • JonBJ JonB

                              @ManiRon
                              So read up how qDebug() displays a QByteArray (as well as a QString)!!
                              Something even as old as https://www.qtcentre.org/threads/54236-qDebug-donsn-t-display-0x00?p=243053#post243053 will presumably do you.....

                              ManiRonM Offline
                              ManiRonM Offline
                              ManiRon
                              wrote on last edited by ManiRon
                              #33

                              @JonB

                              Yes sir i can understand that it will take NUL as a terminate . Is there any way that i can store the full data along with the NUL

                              Christian EhrlicherC 1 Reply Last reply
                              0
                              • ManiRonM ManiRon

                                @JonB

                                Yes sir i can understand that it will take NUL as a terminate . Is there any way that i can store the full data along with the NUL

                                Christian EhrlicherC Online
                                Christian EhrlicherC Online
                                Christian Ehrlicher
                                Lifetime Qt Champion
                                wrote on last edited by
                                #34

                                @ManiRon said in How to make QFile read the whole line:

                                Is there any way that i can store the full data along with the NUL

                                It is stored, just qDebug() stops it's output when it sees NUL. Take a look at the link @JonB provided above.

                                Qt Online Installer direct download: https://download.qt.io/official_releases/online_installers/
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                                ManiRonM 1 Reply Last reply
                                3
                                • Christian EhrlicherC Christian Ehrlicher

                                  @ManiRon said in How to make QFile read the whole line:

                                  Is there any way that i can store the full data along with the NUL

                                  It is stored, just qDebug() stops it's output when it sees NUL. Take a look at the link @JonB provided above.

                                  ManiRonM Offline
                                  ManiRonM Offline
                                  ManiRon
                                  wrote on last edited by
                                  #35

                                  @Christian-Ehrlicher sir i checked the data are read from the file fully but the problem is the way i store . I tried to store it in a QByteArray variable, a char array Variable, a QString Variable but all are terminating when the data has a NUL Inbetween, Now its not the problem of qDebug .

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                                  • Christian EhrlicherC Online
                                    Christian EhrlicherC Online
                                    Christian Ehrlicher
                                    Lifetime Qt Champion
                                    wrote on last edited by
                                    #36

                                    You really should try to understand what we wrote. When you QFile::read() returns exactly the size of the file then all bytes are read and stored in the QByteArray. Just because qDebug() stops at NUL doesn't mean there is no data after that...

                                    Qt Online Installer direct download: https://download.qt.io/official_releases/online_installers/
                                    Visit the Qt Academy at https://academy.qt.io/catalog

                                    ManiRonM 1 Reply Last reply
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                                    • Christian EhrlicherC Christian Ehrlicher

                                      You really should try to understand what we wrote. When you QFile::read() returns exactly the size of the file then all bytes are read and stored in the QByteArray. Just because qDebug() stops at NUL doesn't mean there is no data after that...

                                      ManiRonM Offline
                                      ManiRonM Offline
                                      ManiRon
                                      wrote on last edited by ManiRon
                                      #37

                                      @Christian-Ehrlicher

                                      ok sir, But i tried to write the data what ever i stored in a QBytearray to another file and the result was same . Thats why i concluded that QByteArray terminate at NUL and its mentioned
                                      here
                                      http://doc.qt.io/qt-5/qbytearray.html#details

                                      J.HilkJ 1 Reply Last reply
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                                      • ManiRonM ManiRon

                                        @Christian-Ehrlicher

                                        ok sir, But i tried to write the data what ever i stored in a QBytearray to another file and the result was same . Thats why i concluded that QByteArray terminate at NUL and its mentioned
                                        here
                                        http://doc.qt.io/qt-5/qbytearray.html#details

                                        J.HilkJ Offline
                                        J.HilkJ Offline
                                        J.Hilk
                                        Moderators
                                        wrote on last edited by J.Hilk
                                        #38

                                        @ManiRon said in How to make QFile read the whole line:

                                        @Christian-Ehrlicher

                                        ok sir, But i tried to write the data what ever i stored in a QBytearray to another file and the result was same . Thats why i concluded that QByteArray terminate at NUL and its mentioned
                                        here
                                        http://doc.qt.io/qt-5/qbytearray.html#details

                                        where exactly ?
                                        because the docu clearly sates otherwise and, thats in the section you linked!

                                        ->
                                        0_1542352803222_1ca28d44-9917-4c44-89dc-0ae3b23ac891-image.png


                                        Be aware of the Qt Code of Conduct, when posting : https://forum.qt.io/topic/113070/qt-code-of-conduct


                                        Q: What's that?
                                        A: It's blue light.
                                        Q: What does it do?
                                        A: It turns blue.

                                        ManiRonM 1 Reply Last reply
                                        2
                                        • J.HilkJ J.Hilk

                                          @ManiRon said in How to make QFile read the whole line:

                                          @Christian-Ehrlicher

                                          ok sir, But i tried to write the data what ever i stored in a QBytearray to another file and the result was same . Thats why i concluded that QByteArray terminate at NUL and its mentioned
                                          here
                                          http://doc.qt.io/qt-5/qbytearray.html#details

                                          where exactly ?
                                          because the docu clearly sates otherwise and, thats in the section you linked!

                                          ->
                                          0_1542352803222_1ca28d44-9917-4c44-89dc-0ae3b23ac891-image.png

                                          ManiRonM Offline
                                          ManiRonM Offline
                                          ManiRon
                                          wrote on last edited by
                                          #39

                                          @J.Hilk 0_1542353448743_Capture.JPG

                                          In this line its mentioned

                                          JonBJ 1 Reply Last reply
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