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executing cmd.exe with some console application

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  • R Offline
    R Offline
    Robert M.
    wrote on last edited by
    #5

    I know how to do it in Linux, my solution works fine in Linux. I do not know how to do it in Windows.

    JonBJ 2 Replies Last reply
    0
    • R Robert M.

      I know how to do it in Linux, my solution works fine in Linux. I do not know how to do it in Windows.

      JonBJ Offline
      JonBJ Offline
      JonB
      wrote on last edited by
      #6

      @Robert-M
      What is your solution which works in Linux then?

      I suggested the ways you can do it in Windows. Sorry if that's not what you wanted to hear or if Windows/cmd does not work the way you would like it to.

      R 1 Reply Last reply
      0
      • R Robert M.

        I know how to do it in Linux, my solution works fine in Linux. I do not know how to do it in Windows.

        JonBJ Offline
        JonBJ Offline
        JonB
        wrote on last edited by JonB
        #7

        @Robert-M
        There may be a way to get Qt's QProcess to control the arguments being passed to Windows CreateProcess, which I said you will need to do in order to have it create a new console for the sub-process. Have a look at void QProcess::setCreateProcessArgumentsModifier(QProcess::CreateProcessArgumentModifier modifier) and the discussion at typedef QProcess::CreateProcessArgumentModifier. I have not tried it, but in the sample code there I see

        args->flags |= CREATE_NEW_CONSOLE;
        

        Try that, and then try it for your pause command. You may, or may not, need the cmd /k it shows there rather than cmd /c, depending what you want to happen about the console when your command finishes.

        Note that what you will want/expect to happen to the console after your command executes will depend on what command you are issuing. Likely not the same for echo versus pause.

        1 Reply Last reply
        1
        • R Offline
          R Offline
          Robert M.
          wrote on last edited by
          #8

          I tried (according to Qt documentation):

          QProcess process;
          process.setCreateProcessArgumentsModifier([] (QProcess::CreateProcessArguments *args)
             {
                 args->flags |= CREATE_NEW_CONSOLE;
                 args->startupInfo->dwFlags &= ~STARTF_USESTDHANDLES;
                 args->startupInfo->dwFlags |= STARTF_USEFILLATTRIBUTE;
                 args->startupInfo->dwFillAttribute = BACKGROUND_BLUE | FOREGROUND_RED
                                                    | FOREGROUND_INTENSITY;
             });
          process.start("C:\\Windows\\System32\\cmd.exe", QStringList() << "/c" << "pause");
          

          but it does not display console window. Using /k instead of /c does not help.

          1 Reply Last reply
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          • JonBJ JonB

            @Robert-M
            What is your solution which works in Linux then?

            I suggested the ways you can do it in Windows. Sorry if that's not what you wanted to hear or if Windows/cmd does not work the way you would like it to.

            R Offline
            R Offline
            Robert M.
            wrote on last edited by
            #9

            In Linux I call process->start(...) with xterm.

            R 1 Reply Last reply
            0
            • VRoninV Offline
              VRoninV Offline
              VRonin
              wrote on last edited by
              #10

              Did you try using startDetached instead of start?

              "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

              R JonBJ 2 Replies Last reply
              2
              • VRoninV VRonin

                Did you try using startDetached instead of start?

                R Offline
                R Offline
                Robert M.
                wrote on last edited by
                #11

                You are great! Thanks a lot!

                process.setProgram("C:\\Windows\\System32\\cmd.exe");
                process.setArguments({"/k", "pause"});
                qint64 pid;
                process.startDetached(&pid);
                

                displays console with pause text.

                1 Reply Last reply
                0
                • VRoninV VRonin

                  Did you try using startDetached instead of start?

                  JonBJ Offline
                  JonBJ Offline
                  JonB
                  wrote on last edited by
                  #12

                  @VRonin said in executing cmd.exe with some console application:

                  Did you try using startDetached instead of start?

                  Interesting. But why does that allow the new console where start does not? :)

                  1 Reply Last reply
                  0
                  • VRoninV Offline
                    VRoninV Offline
                    VRonin
                    wrote on last edited by VRonin
                    #13

                    start is designed explicitly to avoid popping new consoles up, see the comment block in https://code.woboq.org/qt5/qtbase/src/corelib/io/qprocess_win.cpp.html#550

                    we [...] do not want console tools launched from a GUI app to create new console windows (behavior consistent with UNIX).

                    "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

                    JonBJ 2 Replies Last reply
                    2
                    • VRoninV VRonin

                      start is designed explicitly to avoid popping new consoles up, see the comment block in https://code.woboq.org/qt5/qtbase/src/corelib/io/qprocess_win.cpp.html#550

                      we [...] do not want console tools launched from a GUI app to create new console windows (behavior consistent with UNIX).

                      JonBJ Offline
                      JonBJ Offline
                      JonB
                      wrote on last edited by JonB
                      #14

                      @VRonin said in executing cmd.exe with some console application:

                      see the comment block in https://code.woboq.org/qt5/qtbase/src/corelib/io/qprocess_win.cpp.html#550

                      // However, we also do not want console tools launched from a GUI app to
                      // create new console windows (behavior consistent with UNIX).
                      DWORD dwCreationFlags = (GetConsoleWindow() ? 0 : CREATE_NO_WINDOW);
                      

                      Well no wonder then :) But we don't get told this is a difference from startDetached() :) I will try to remember this for the future.

                      P.S.
                      Isn't just lovely to see UNIX written? :)

                      1 Reply Last reply
                      0
                      • VRoninV VRonin

                        start is designed explicitly to avoid popping new consoles up, see the comment block in https://code.woboq.org/qt5/qtbase/src/corelib/io/qprocess_win.cpp.html#550

                        we [...] do not want console tools launched from a GUI app to create new console windows (behavior consistent with UNIX).

                        JonBJ Offline
                        JonBJ Offline
                        JonB
                        wrote on last edited by JonB
                        #15

                        @VRonin said in executing cmd.exe with some console application:

                        start is designed explicitly to avoid popping new consoles u

                        Not tested, but can't you change this in the same way in your setCreateProcessArgumentsModifier() anyway, just add the first line to whatever you want:

                        args->flags &= ~CREATE_NO_WINDOW;  // switch that *off*
                        args->flags |= CREATE_NEW_CONSOLE;
                        ...
                        

                        ?

                        If this works for start() like the OP says it apparently is working for startDetached() the advantage is you can still wait for sub-process completion, if desired.

                        1 Reply Last reply
                        2
                        • VRoninV Offline
                          VRoninV Offline
                          VRonin
                          wrote on last edited by
                          #16

                          Indeed you can!

                          "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

                          1 Reply Last reply
                          1
                          • R Robert M.

                            In Linux I call process->start(...) with xterm.

                            R Offline
                            R Offline
                            Robert M.
                            wrote on last edited by VRonin
                            #17

                            I have one problem in Linux. I invoke xterm with dirtyphp.sh script:

                                QProcess process;
                                QString exec = QString::fromStdString(terminal);
                                QStringList params;
                                params << "-hold" << "-e"; 
                                bool p0 = true;
                                for (std::string s : explode(std::string(" "), dirtyphp_command)) {
                                    if (p0) {
                                        std::string s0 = str_replace("'", "", s) + ".sh";
                                        params << s0.c_str();
                                        p0 = false;
                                    } else {
                                        params << str_replace("'", "", s).c_str();
                                    }
                                }
                                process.start(exec, params);
                                process.waitForFinished();
                            

                            In dirtyphp.sh script I am waiting for CTRL+C at the end:

                            d=`dirname $0`
                            if [ "$d" = "" ]
                            then
                            	d="."
                            fi
                            $d/dirtyphp $@
                            echo 'Hit CTRL+C';
                            while true 
                            do
                            	sleep 1
                            done 
                            

                            The problem is that xterm window is closed automatically without waiting for CTRL+C and the user cannot browse output produced by program dirtyphp in xterm window. I do not understand why - the loop and the end of dirtyphp.sh script should be infinite.

                            JonBJ 1 Reply Last reply
                            0
                            • R Robert M.

                              I have one problem in Linux. I invoke xterm with dirtyphp.sh script:

                                  QProcess process;
                                  QString exec = QString::fromStdString(terminal);
                                  QStringList params;
                                  params << "-hold" << "-e"; 
                                  bool p0 = true;
                                  for (std::string s : explode(std::string(" "), dirtyphp_command)) {
                                      if (p0) {
                                          std::string s0 = str_replace("'", "", s) + ".sh";
                                          params << s0.c_str();
                                          p0 = false;
                                      } else {
                                          params << str_replace("'", "", s).c_str();
                                      }
                                  }
                                  process.start(exec, params);
                                  process.waitForFinished();
                              

                              In dirtyphp.sh script I am waiting for CTRL+C at the end:

                              d=`dirname $0`
                              if [ "$d" = "" ]
                              then
                              	d="."
                              fi
                              $d/dirtyphp $@
                              echo 'Hit CTRL+C';
                              while true 
                              do
                              	sleep 1
                              done 
                              

                              The problem is that xterm window is closed automatically without waiting for CTRL+C and the user cannot browse output produced by program dirtyphp in xterm window. I do not understand why - the loop and the end of dirtyphp.sh script should be infinite.

                              JonBJ Offline
                              JonBJ Offline
                              JonB
                              wrote on last edited by JonB
                              #18

                              @Robert-M
                              If you think it's even executing that script and getting as far as the while true loop (goodness knows), put some debugging into the loop, like an echo or a read.

                              Or maybe put a set -x at the start of the script so you can see what is going on?

                              1 Reply Last reply
                              0
                              • R Offline
                                R Offline
                                Robert M.
                                wrote on last edited by
                                #19

                                I changed the loop to the following:
                                while true
                                do
                                echo -n _
                                done
                                I see no underscores in xterm window.
                                Qt reports:
                                QProcess: Destroyed while process ("xterm") is still running.
                                I modified waitForFinish call:
                                process.waitForFinish(-1);
                                and now I can see underscores.
                                Problem solved.

                                JonBJ 1 Reply Last reply
                                0
                                • R Robert M.

                                  I changed the loop to the following:
                                  while true
                                  do
                                  echo -n _
                                  done
                                  I see no underscores in xterm window.
                                  Qt reports:
                                  QProcess: Destroyed while process ("xterm") is still running.
                                  I modified waitForFinish call:
                                  process.waitForFinish(-1);
                                  and now I can see underscores.
                                  Problem solved.

                                  JonBJ Offline
                                  JonBJ Offline
                                  JonB
                                  wrote on last edited by JonB
                                  #20

                                  @Robert-M
                                  bool QProcess::waitForFinished(int msecs = 30000) means that waitForFinished() only waits up to 30 seconds, and then your QProcess process; goes out of scope and causes the error. If your sub-process takes longer that is why you wanted waitForFinished(-1).

                                  1 Reply Last reply
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