how to communicate qprocess with QTCP socket?
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In my GUI application,My exe is a application that runs forever . untill the user stop it. actually , i can run and communicate with my exe using command in terminal. i want GUI for that.
i have two button start and stop. In start , i am using Qprocess. so the processes run in background.
it's nice upto here. but i want to pass a command to exe and receive the reply from the exe.
start_button{
//exe should run forever
}stop_button{
//stop the execution of exe
}In start_button function , I am using Qprocess to execute the exe. Now i can run my exe background.
how do i communicate with exe?@raghava said in how to communicate qprocess with QTCP socket?:
i can run and communicate with my exe using command in terminal
What does that mean? Do you mean: you can type things in with the keyboard while it's running and it reads what you've entered and acts on it (perhaps producing output back)? Or, do you run
yourapp.exe <some argument>repeatedly? Or what? -
@JonB
my exe runs continously,In terminal,
./myexe<enter>
my application start
after running for 1 minute of running, wait for user command .if i give some command like:
power<enter> , then it display power level
timestamp<enter>, then it display time.are you understanding what i am saying?
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@JonB
my exe runs continously,In terminal,
./myexe<enter>
my application start
after running for 1 minute of running, wait for user command .if i give some command like:
power<enter> , then it display power level
timestamp<enter>, then it display time.are you understanding what i am saying?
@raghava
OK, so now you are saying you run an application and it continuously reads fromstdin, and responds by writing tostdout.Then should be no need for TCP. Your parent process (which creates the
QProcess) can write to child'sstdinviaprocess->write()to send its "commands", and can read back from child's "response" tostdout/stderrvia one of theQProcess::read...()methods (probably inside theQProcess::readyRead...()slots for signals).BTW, this approach will only work if you launch your sub-process via
QProcess::start(), not if you want to useQProcess::startDetached(). -
In my GUI application,My exe is a application that runs forever . untill the user stop it. actually , i can run and communicate with my exe using command in terminal. i want GUI for that.
i have two button start and stop. In start , i am using Qprocess. so the processes run in background.
it's nice upto here. but i want to pass a command to exe and receive the reply from the exe.
start_button{
//exe should run forever
}stop_button{
//stop the execution of exe
}In start_button function , I am using Qprocess to execute the exe. Now i can run my exe background.
how do i communicate with exe?@raghava said in how to communicate qprocess with QTCP socket?:
but i want to pass a command to exe and receive the reply from the exe
Do what @VRonin suggested then: use stdin/stdout. You can see how to do it in QProcess documentation.
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@raghava said in how to communicate qprocess with QTCP socket?:
but i want to pass a command to exe and receive the reply from the exe
Do what @VRonin suggested then: use stdin/stdout. You can see how to do it in QProcess documentation.
@jsulm
If he does as @VRonin , as you just suggested, he will have to start using TCP. He has said he does not want to do that, so why can't he use no TCP and stdin/stdout simply just as I suggested?can you please elaborate you answer.
If you mean, can I write code for you, I'm afraid i am not a Qt support person. I'm just a user who tries to give hints here, and I have loads of my own work which I really ought to be doing instead...! :)
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@jsulm
If he does as @VRonin , as you just suggested, he will have to start using TCP. He has said he does not want to do that, so why can't he use no TCP and stdin/stdout simply just as I suggested?can you please elaborate you answer.
If you mean, can I write code for you, I'm afraid i am not a Qt support person. I'm just a user who tries to give hints here, and I have loads of my own work which I really ought to be doing instead...! :)
@JonB said in how to communicate qprocess with QTCP socket?:
If he does as @VRonin , as you just suggested, he will have to start using TCP
How is reading/writing from/to stdin/stdout related to TCP?
It is as simple as http://doc.qt.io/qt-5/qprocess.html#readAllStandardOutput and http://doc.qt.io/qt-5/qiodevice.html#write -
@JonB said in how to communicate qprocess with QTCP socket?:
If he does as @VRonin , as you just suggested, he will have to start using TCP
How is reading/writing from/to stdin/stdout related to TCP?
It is as simple as http://doc.qt.io/qt-5/qprocess.html#readAllStandardOutput and http://doc.qt.io/qt-5/qiodevice.html#writeVRonin about 2 hours ago
I'd say QLocalSocket is more appropriate than QTcpSocket
You can use std::cin/std::cout to make the two programs dialogue see http://doc.qt.io/qt-5/qprocess.html#communicating-via-channelsThat's what I meant. I shouldn't have said "TCP", I should have said "Socket". Why does he need to use any socket stuff to emulate interacting with an application which presently works purely via stdin/stdout to the terminal, which is all I'm suggesting he do through
QProcess? Perhaps there's a misunderstanding. -
VRonin about 2 hours ago
I'd say QLocalSocket is more appropriate than QTcpSocket
You can use std::cin/std::cout to make the two programs dialogue see http://doc.qt.io/qt-5/qprocess.html#communicating-via-channelsThat's what I meant. I shouldn't have said "TCP", I should have said "Socket". Why does he need to use any socket stuff to emulate interacting with an application which presently works purely via stdin/stdout to the terminal, which is all I'm suggesting he do through
QProcess? Perhaps there's a misunderstanding.@JonB I'm talking about point 2 from @VRonin
"2. You can use std::cin/std::cout to make the two programs dialogue see http://doc.qt.io/qt-5/qprocess.html#communicating-via-channels" -
@JonB I'm talking about point 2 from @VRonin
"2. You can use std::cin/std::cout to make the two programs dialogue see http://doc.qt.io/qt-5/qprocess.html#communicating-via-channels"@jsulm
Ahhh, OK! :)Yes, he can change over to using C++'s std::cin/std::cout if he wants. I just do it directly via
QProcess::read/writefrom my Python. They come to the same for the OP: he is attaching stdin/stdouts between parent & child, whichever way you look at it. And no sockets :)
