High scale chat server - C / C++ / MFC Discussion Boards

Hans Ruck1-Jul-02 2:36

1-Jul-02 2:36

Unfortunately, killing the process is impossible because the access is denied.
I don't know how do you kill your process all the time but anyway i can't do it because i have to unload some resources on processing stop signal.
I will reboot.

rechi

Re: ATL service stopping

Bill Wilson1-Jul-02 9:38

Bill Wilson

1-Jul-02 9:38

From the task manager, choose Debug instead of End Process. Once you are in the debugger, you can kill it with Stop Debugging from the Debug menu.

Thanks for the help,
Bill

How to prevent a CFileDialog Box from resizing?

Erik1-Jul-02 2:06

Erik

1-Jul-02 2:06

Hello,

I use an instance of a CFileDialogBox whenever a user saves or loads a file in my application. For some reason, I need the Dialog Box to be a fixed size when loading files, since I have implemented some additional preview features to that box.

However, when a user selects the "save as" CFileDialogBox (which is another instance, of course), and resizes that box, windows somehow saves the size of that Dialog box. When the user now tries to load a file, that instance of CFileDialogBox is displayed at exactly the same size the Save-As Box was resized to.

Why does windows memorize the size of the dialog, and how can I resize the next instance of CFileDialog to its default value (i.e. the value it uses when I start my application)?

I would like to prevent that behaviour, always displaying my File-Open box at the system default standard size. Any suggestions on how to achieve this?

TIA,

Erik.

Re: How to prevent a CFileDialog Box from resizing?

Prem Kumar1-Jul-02 4:51

Prem Kumar

1-Jul-02 4:51

I think you have created your own dialog class deriving
from CFileDialog. You can override the 'OnSize' and
then set what ever size you want and then change the
window style to non-resizable by using
SetWindowLong.

Re: How to prevent a CFileDialog Box from resizing?

Erik1-Jul-02 19:02

Erik

1-Jul-02 19:02

Hi Prem,

I was thinking of that, too. However, how can I determine the original size of the file-open dialog given by the os in my derived class?

TIA,

Erik.

I/O Completion Port

unknown soldier1-Jul-02 0:59

unknown soldier

1-Jul-02 0:59

Worker threads are associated with I/O completion port. Whenever I/O operation completed a thread is invoked. Now when this thread is invoked, how we come to know that which "type" of operation completed whether "read" or write". I think this has to be determined by overlapped structure but i don't know that which "field" of this structure informs about the "type" of operation completed.

Re: I/O Completion Port

Len Holgate1-Jul-02 8:53

Len Holgate

1-Jul-02 8:53

bakhtawar wrote:
Worker threads are associated with I/O completion port. Whenever I/O operation completed a thread is invoked. Now when this thread is invoked, how we come to know that which "type" of operation completed whether "read" or write". I think this has to be determined by overlapped structure but i don't know that which "field" of this structure informs about the "type" of operation completed.

What usually happens is that you don't actually pass only an "overlapped" structure, you pass something that has an overlapped structure in it and also contains other stuff. This allows you to pass anything you like to your thread. Then, once inside your thread you simply convert back from the pointer to the portion of your structure that is an "overlapped" to a pointer to your structure.

If you're using C++ then you might define your overlapped like this:

<br />
class MyOverlapped : public OVERLAPPED<br />
{<br />
   // include your own data here.<br />
};<br />

And then pass it to a read request like this:

<br />
MyOverlapped *pBuffer;<br />
<br />
   if (SOCKET_ERROR == ::WSARecv(<br />
      pSocket->m_socket, <br />
      pBuffer->GetWSABUF(), <br />
      1, <br />
      &dwNumBytes,<br />
      &dwFlags,<br />
      pBuffer, <br />
      NULL))<br />

and retrieve it from

<br />
   MyOverlapped *pBuffer = 0;<br />
<br />
   GetQueuedCompletionStatus(m_iocp, &dwIoSize, (PDWORD_PTR)&pSocket, (OVERLAPPED**)&pBuffer);<br />

See the code for my reusable C++ socket server class for full details.

Len Holgate
www.jetbyte.com
The right code, right now.

High scale chat server

1-Jul-02 0:47

I am looking for any open source project regarding "highly scalable" chat server deleaing with 5000+ clients. No matter it'll be in distributed environment or standalone environment.

If any one knows about such project then please inform me. Also I'll be grateful if some one give me advice for creating a chat server that deals with "large" number of clients. I'll be using I/O completion ports but i want the response time as quick as MSN server when too many clients attached. Infact the server is also linked with database server for providing lists of authorized buddies to clients just like MSN server. Your advice is most welcome.

Re: High scale chat server

benjymous1-Jul-02 2:02

benjymous

1-Jul-02 2:02

IRC? (Using chanserv and nickserv)

--
Help me! I'm turning into a grapefruit!

Re: High scale chat server

Len Holgate1-Jul-02 9:01

Len Holgate

1-Jul-02 9:01

Sunugtufiq Chang wrote:
I am looking for any open source project regarding "highly scalable" chat server deleaing with 5000+ clients. No matter it'll be in distributed environment or standalone environment.

Take a look at my articles on high performance IO completion port based TCP servers. You'll need to make sure that your database IO doesn't happen on your socket IO threads or you'll kill your scalability, but the 2nd article deals with that issue.

You could probably trim some fat from the servers that I present in the article as they're designed for reuse, and that's probably at odds with actually being the fastest possible...

Then, if they you still cant handle the required load with your target hardware you probably need to scale out and use a cluster of machines sharing the one IP address (in the same way that high performance web farms are constructed) but that's left as an exercise for the reader Wink | ;)

Len Holgate
www.jetbyte.com
The right code, right now.

Get code page of exe

ed welch30-Jun-02 23:08

ed welch

30-Jun-02 23:08

The code page that a program uses is specified in the resource file, using the the #pragma code_page() command.
Is there any way of querying this information from the program at run time?

Re: Get code page of exe

Mike Nordell2-Jul-02 7:20

Mike Nordell

2-Jul-02 7:20

Have a look at VERSIONINFO and work your way from there.

Can I use standard FTP command to check file properties on remote site?

DengJW30-Jun-02 23:08

DengJW

30-Jun-02 23:08

What I am doing is to put some files to remote site. Before using 'put' command, I want to check whether the file to be transferred, which is located on local site, is newer than the file with the same name on the remote site.
Only standard command should be used.

This Q might not be put here, but I could not find an appropriate board for it, sorry ...

DJ

My dialog window doesn't process my accellerator keys?

solosnake30-Jun-02 22:54

solosnake

30-Jun-02 22:54

Hello all

I have a feeling I have done something wrong in building my application because all of my problems seem to be stemmingf rom the same root cause, which I dont know how to fix Frown | :(

I have an MFC application, and it has a MainFrame, with a CView etc. The Main frame has a member dialog window, kept permanantly open and visible. It is created as follows:

bToolbarOkay = m_wndSettings.Create(this, IDD_SETTINGS2,WS_CHILD|WS_VISIBLE|CBRS_RIGHT|CBRS_GRIPPER|CBRS_TOOLTIPS|CBRS_FLYBY|CBRS_SIZE_DYNAMIC,0);

I have an accellerator table which is working fine, UNTIL the user clicks on a control in the settings dialog window. Once he/she has done this, the dialog window seems to be in control of everything. My problem is that it is logical to allow the user to change settings in this dialog, and to allow him/her to tab between controls within the window, but keping the focus there is ruining my accellerator?? How can I get the dialog window to play nicely with my accellerator table?

Any thoughts?

Thanks for all help,

solosnake

Re: My dialog window doesn't process my accellerator keys?

Prem Kumar1-Jul-02 4:56

Prem Kumar

1-Jul-02 4:56

Obviously the way the application is behaving correctly.
Only the current window that has the focus should process
the Accelerator Keys.

But any way if you still want to chain it to the main frame
override the PreTranslateMessage in the Dialog and
call the CMainFrame's PreTranslateMessage.

But i must warn you that if you have any common key strokes
(most probably with Alt combination) the dialog may not
process them.

Whether 'Control' Key is pressed ?

nilaysoft30-Jun-02 22:41

nilaysoft

30-Jun-02 22:41

I response the WM_KEYDOWND message to shift my view if the arrow keys are pressed, while the moving speed should be faster if Control key is pressed simultaneously. This line of code is used:

case VK_LEFT: 
case VK_RIGHT: 
if (GetKeyState(VK_CONTROL) == -128 || GetKeyState(VK_CONTROL) == -127)
{
   // Do somthing here.
}

I do think there should exist a better way than this stupid one, do you know that?

Re: Whether 'Control' Key is pressed ?

30-Jun-02 23:29

I think the code can't work.Unlike "shift" key,you can't catch the "control"
key in the WM_KEYDOWN.You should handle it in PreTranslateMessage().

//Do the Ctrl+A action
BOOL C***::PreTranslateMessage(MSG* pMsg)
{
if( pMsg->message == WM_KEYDOWN )
{
int vkey = pMsg->wParam;
if( vkey == 'A' )
{
if( GetKeyState( VK_CONTROL ) & 0x8000 )
SelectAll();
}
}
return CBase***::PreTranslateMessage( pMsg );
}

Chreers

Re: Whether 'Control' Key is pressed ?

Mustafa Demirhan1-Jul-02 7:09

Mustafa Demirhan

1-Jul-02 7:09

Use GetAsyncKeyState instead...

Mustafa Demirhan
http://www.macroangel.com
Sonork ID 100.9935:zoltrix

CHtmlView Bug?

Renegade30-Jun-02 22:38

Renegade

30-Jun-02 22:38

Hi there,

If i generate an SDI application using CHtmlView and then try to display an
ActiveX Document developed in VB in the view then it seems that certain controls aren't repainted properly if the view is resized or is repainted.
For example, the borders of a ListControl or ComboBox in the ActiveX Documnet aren't repainted properly. Any suggestions?

DLL's

urid30-Jun-02 22:32

urid

30-Jun-02 22:32

I create some object in the dll and return from dll pointer to this object
but when i try to do with this pointer some operation for exemple get name of object that return CString address of this pointer not valid , may be dll return pointer to local dll address , becose usially from dll i receive 0x00000001 address for pointer and it not seem6 for me ok.How can i receive from dll valid pointer to object . Unsure | :~

How to get informations from other process

Neil Yao30-Jun-02 22:31

Neil Yao

30-Jun-02 22:31

I want to use ListView_GetItem to read item informations of the ListView. And when this listview control is created in other process, the call failed, why? when I send message to button or edit or other simple controls in another process, everything goes well. somebody help me! Cry | :((

Re: How to get informations from other process

Prem Kumar1-Jul-02 0:25

Prem Kumar

1-Jul-02 0:25

The new common controls' handles are not thread safe. The handles
are only valid in that process in which they are created.

As for the older controls microsoft supports them because
the old 16-bit code used a lot of this type of programming.
But the newer controls do not support that type of programming.

Re: How to get informations from other process

Neil Yao1-Jul-02 15:03

Neil Yao

1-Jul-02 15:03

Thank you! I have found the solution in MSDN.

Force a tooltip

Davy Mitchell30-Jun-02 22:06

Davy Mitchell

30-Jun-02 22:06

Hi Folks,

I am using the free Dundas tooltip class from Codeproject. I am using it with a ListCtrl and I want a tooltip to appear when the selection changes.

How can I do this? BTW the class is excellent - well done Dundas!

Cheers,

Davy
http://www.LateDecember.com

Re: Force a tooltip

Peter Zajac10-Jul-02 8:05

Peter Zajac

10-Jul-02 8:05

Hi,

The Dundas ToolTip control that you have mentioned was not designed to perform the functionality that you are looking for. I was able however to achieve this behavior with simple change to the source code.

Please send me an email and I will be able to provide you with more information.

Peter Zajac
Dundas Technical Support

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.