Explanation on the use of qpprocess

QProcess There are two usage patterns ：

• One is to call start() or execute()： At this time, the standard input of the called function 、 standard output 、 Standard error Have been redirected to QProcess In the corresponding pipe created . under these circumstances , Even if your console program has its own Console, Then it can neither receive any input , Nothing will be output . The parent process of the change process is still our own current process , therefore , It can be controlled .（ So it's also called Controllable mode ）

that , In this mode , If you expect to see a console window that should belong to it , Just follow me dev c++ Wait for the result of software compilation and operation , How does that need to be done ：

Add a line of code ：

    process1.setCreateProcessArgumentsModifier(
                [](QProcess::CreateProcessArguments *args) {
        args->flags |= CREATE_NEW_CONSOLE;
        args->startupInfo->dwFlags &=~ STARTF_USESTDHANDLES;
    });

principle ： because QProcess The underlying call is windows The underlying Library of the platform Win32 API function  CreateProcess()  To create sub processes , And default to CreateProcess() In the arguments of the function , It indicates that the console window should not appear , So we want to show the console window , You need to modify the default to CreateProcess() The parameters of the function , It is realized through the above function .

And the subprocess will share This window of the parent process sets properties , Such as process A The setting starts the process by displaying the console window B, Input to B Among the parameters of is the process C The path of , Only one console window will appear , That's the process C The content of will be displayed in the process B In the console window .

Sample code ：

    QStringList arguments;
    arguments;//
    
    QProcess process1(this);
    process1.setCreateProcessArgumentsModifier(
                [](QProcess::CreateProcessArguments *args) {
        args->flags |= CREATE_NEW_CONSOLE;
        args->startupInfo->dwFlags &=~ STARTF_USESTDHANDLES;
    });
    process1.start("C:\\Users\\86132\\Documents\\panda_project\\test1.exe"/*,arguments*/);
    process1.waitForStarted();
    process1.waitForFinished();

reference ：

QProcess Calling an external program does not display the interface - sagerking - Blog Garden

QProcess :: startDetached Start up cmd.exe External programs have no pop-up windows _xinqingwuji The blog of - Programmer baby - Programmer baby

Windows order QProcess eject CMD Interface _Sudouble The blog of -CSDN Blog

• Another usage is ,startDetached()： This is a QProcess After starting your console program , There is no additional operation , You can't control it in the current program （ It is an independent process , The parent process is not the current process , Therefore, it cannot be controlled ）. however , stay Windows Next , There will be one you expect Console appear ; In other systems , There will be no terminal display .（ Uncontrollable mode ）

notes ：

• Usually in English documents ,fine-tune It means fine-tuning , Such as parameter tuning
• passing it to Indicates that the xx Pass to xx, It's about delivering , Input meaning
•  custom color scheme, Represents a custom color scheme ,custom It generally means custom , For example, software custom installation options

reference ：

Qt And ：QProcess Use summary _ A blog that stands tall and strong without desire -CSDN Blog _qprocess