LITTLEBLACKDOG.COM

Stray Dog Joined: 20 Mar 2003 Posts: 41

Hi ppl,

I'm quite new to windows API and want u guyz to give me some help here, thanz really!!

I have a main window now and I created 6 child windows, each for running an executable C program.
I have 6 C programs which are actually socket programs. They talk to each other using TCP .

What I'm doing now is simply use a child window to display the input and output messages of these 6 C programs (like TextOut and input for these 6 programs).

The main window there is just for grouping the 6 child windows together to make it more convenient. So I think there won't be any message loop for the main window. Just creating the child windows. And the child windows will execute the C programs. These C programs will run and output messages to their own child window like a screen and get input from their corresponding child window.

So If I have A B C D E F for the executable C programs. I will also have child windows A B C D E F and these 6 child windows will be created by the main window. And the input and ouput of messages on the screen of child window A will be all handled by the .exe of program A.

What I wanna ask is...is this possible at all? And how do I actually implement this? I think the complicated part is how do those 6 programs handle the in and out of messages on the screen of their own child window? Shocked

Not sure I make it clear coz I am always lack of organization, so if you don't understand my design, just drop me a few lines, thanz so much!! Very Happy

Posted: Mon May 05, 2003 6:30 am Post subject:

are you using threads for each separate program? have you written these separate programs, or are they precompiled? are you using MFC, Win32, or what to build your GUI? are you capturing standard output, or are you writing to some other buffer?

Posted: Mon May 05, 2003 6:31 am Post subject:

is this the same program as before, or a new program?

Posted: Mon May 05, 2003 6:33 am Post subject:

you could always write a batch file:

Code: Select all

a &


b &


c &


d &


e &


f &

and use explorer as your "single window"

Stray Dog Joined: 20 Mar 2003 Posts: 41

I am not using therad for the separate program, actually it's just I want to run these 6 executable C programs (that's after compiled, producing .exe) in the child windows. You can suggest me to do in some other ways. Very Happy

But I would love to separate these programs as much as possible as I said they are representing different parties, talking to each other through TCP. Having them inside a main window is not that good already, blurring the orginial idea, if more connections are made between the programs, then the orginial purpose will be lost... Shocked

Yes I have written these separate programs, I have all the source codes, so I can change them, but I want to limit the changes only to the I/Os to the screen of child windows. Like in the command prompt mode for tehse 6 programs, I use printf for output and getchar for input. Then in the GUI, I might be using TextOut for output..but I dunno what should be used for input.. Confused

And yes I am using Win32. capturing standard output? Can I still do that in Win32? Shocked

I really dunno hehe. I wanna hear what u suggest me to do Very Happy

The program...same as before?..um...hard to say...I guess we better treat it as some different ones bcoz I have made changes afterwards.

And I don't get the batch file method, hehe Mr. Green

, can you elaborate more? Thanz really!! Very Happy

Posted: Mon May 05, 2003 7:06 am Post subject:

Each child window will have to call "CreateProcess()" to launch the executable program it's associated with, and then in the child window's message loop it'll read from the console's output. The child window will be in charge of starting and stopping that new process.

So no, you won't be using threads, you'll be using child processes. It'll be just as if you manually started each of the six programs but the child windows are the ones who actually do that work for you. That way you can get a hook between the child window and the console for reading the output.

It's most likely open a new command window which you can hide, but using FindWindow() passing it the text you see in the console window's title bar. That returns an HWND which you can then send it a WM_SHOWWINDOW message with SW_HIDE parameter to hide it. Keep the HWND if you need to use it again later.

When cleaning up and destroying the child window, the child window's destructor should kill the associated process (you C program you attached) if it hasn't ended yet.

Go on MSDN website and read up on the Win32 API functions I've mentioned here.

CreateProcess()
FindWindow()

Stray Dog Joined: 20 Mar 2003 Posts: 41

Lycander wrote:
Each child window will have to call "CreateProcess()" to launch the executable program it's associated with, and then in the child window's message loop it'll read from the console's output. The child window will be in charge of starting and stopping that new process.

So no, you won't be using threads, you'll be using child processes. It'll be just as if you manually started each of the six programs but the child windows are the ones who actually do that work for you. That way you can get a hook between the child window and the console for reading the output.

COOOOOOL!!! Mr. Green

yes yes that's more like it, I think this is just what I need!! Mr. Green

Quote:
It's most likely open a new command window which you can hide, but using FindWindow() passing it the text you see in the console window's title bar. That returns an HWND which you can then send it a WM_SHOWWINDOW message with SW_HIDE parameter to hide it. Keep the HWND if you need to use it again later.

But don't quite get what you mean here Shocked

[edit] Oh...but hold on...you mean I should create child process for those child windows? But I have already created them using MDI Shocked

Posted: Mon May 05, 2003 10:13 am Post subject:

No what I mean is: you said you have 6 different C programs, and they seem to be command line programs which you want 6 child windows to monitor and display output from. So you create a seperate child process for each of those C programs, and in each child window it would monitor that corresponding process.

When you create a new process you get a handle to it, with which you can read from stdout, that's the bit I said to hook up to each corresponding child window. Using MDI as you are now is fine.

Stray Dog Joined: 20 Mar 2003 Posts: 41

So u mean the child process will monitor the input and the parent process will display output? Shocked

But I only allow input at some given times.

Actually it's like this:
I printf "Please enter sth"
and I get the input keyed in by user as "sth"

So it's like those command-line window but it's just I wanna make it an application window coz I wanna add one or two buttons there to make the programs start hehe Mr. Green

Oh but did I misunderstand you? Actually can you list some functions used in a flow? Mr. Green

Think that will make me easier to understand coz I'm not good at logic Laughing

Stray Dog Joined: 20 Mar 2003 Posts: 41

OK I have some progress now Cool

I have created 6 child windows and trying to execute the C executable in these child windows

I am using WinExec but there are only two parameters so how do I pass the child window handle to the command to make the .exe to be run in the specified child window? Shocked

Thanz

[edit] Oh yes....Lycander told me to use CreateProcess().. Shocked

Let me try...

[edit]
Oh...I think what the problem is now, I just made a menu item which is "execute" Lycander should know hehe. and the .exe are called only when the menu is clicked. so...can't start to execute the files right away...so what do u guyz suggest me to do? Shocked

Stray Dog Joined: 20 Mar 2003 Posts: 41

Oh Lycander, got a question here, do I have to use pipes for the processes? Or just create the processes? So the child is to execute the 6 C programs right? But what are the parents doing? Shocked

Posted: Tue May 06, 2003 6:27 am Post subject:

The parents are watching over the children of course Wink

Ok, beyond that pun, the parent window (your MDI parent window) controls any messages not handled by the child windows. And if the parent window is closed, then it sends a destroy message to each of the child window. That's when the child window is responsible for terminating the process which it created.

I believe pipes are go inter-process communications, like reading and writing to each other's console (stdin, stdout).

I uploaded 2 files to my webserver which I've linked below. It's a WinHelp file and the table of contents file. Download them and keep them together in the same folder. It's a great reference that I use from time to time to look up Win32 API functions. I looked breifly thru it and there's some info on creating processes, and how to create/use pipes. Go into the index and type "Pipe" and read all the topics related to it.

http://www.ly-tech.com/win32/WIN32.HLP (~24 MB)
http://www.ly-tech.com/win32/WIN32.CNT (~100 KB)

Rather large download, but worth it!

EDIT: I just realized that clicking on the link and my browser tries to open it in a new window. So just to be sure, you should right click on the link and "Save As..."

Stray Dog Joined: 20 Mar 2003 Posts: 41

Quote:
The parents are watching over the children of course Ok, beyond that pun, the parent window (your MDI parent window) controls any messages not handled by the child windows. And if the parent window is closed, then it sends a destroy message to each of the child window. That's when the child window is responsible for terminating the process which it created.

Oh so you mean the CreateProcess is for creating child windows? Shocked

But I have already created the child windows Very Happy

Or...I misunderstand again... Shocked

hehe

ahhhhhhhh so I really have to use pipes? Sounds like a really hard one...I plan to finish the GUI within a couple of hrs from now...oh...not sure if I have time... Shocked

Actually I don't quite know where to use the pipes....yes I know it's for my little C programs to communicate with my little Windows API program but...well...maybe after I read your help files I'd be more clear hehe

And thanz soooooooooooo much for the files haha Very Happy

me still downloading....really a big file...it's 6X% now.... Mr. Green

But the "win32.cnt" is it just a html? Shocked

[edit] oh...I just read your edit hehe Mr. Green

Stray Dog Joined: 20 Mar 2003 Posts: 41

Oh cool me looking up the help file now
but hey, do you know where I can look at some source codes? Bcoz that would certainly help a lot too, to see how functions are called Mr. Green

Posted: Tue May 06, 2003 7:37 am Post subject:

www.programmersheaven.com

www.codeproject.com