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executing cmd.exe with some console application

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  • 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
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            • 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
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              • 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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