C / C++ / MFC

Re: CSocket new-b question

5-Sep-02 12:36

Hello,
I am trying to make a simple CSocket server that will accept multiple connections on the same port.. Here is what I have done.

On my Accept Connections function I do the following:

CMySocket* pSocket = new CMySocket();
	
pSocket->SetParent(this);

if (m_sListen.Accept(*pSocket))
{
	m_connectionList.AddTail(pSocket);		
}
else
	delete pSocket;

This seems to work.. I can see the m_connectionList grow with each connect..
m_connectionList is a CPtrList.

If only one client connects and sends data, Everything is fine.. Its when Multiple clients connect and I receive data from a client it seems to lock up the server until all the clients disconnect.

I know I am doing this receive function wrong.. How do i figure out what Socket is sending the information so I can receive it???

Here is my receive function

char *pBuf = new char[1025];
CString strRecvd;
int iRcvd;
int iConnections = m_connectionList.GetCount();

POSITION pos = m_connectionList.GetHeadPosition();

while(iConnections > 0)
{
	CMySocket* pSocket = (CMySocket*)m_connectionList.GetNext(pos);
		
	iRcvd = pSocket->Receive(pBuf,1024);
		

	// Did we a error, if not then proceed
	if (iRcvd == SOCKET_ERROR)
	{
		delete[] pBuf;
		AfxMessageBox("Socket error");
	}
	else
	{
        ......
        } 
         iConnections--;
}

I think the problem is in how I am storing the pointers to the Sockets.. but then again, I am new to this so I would be surprised if I am going about this the wrong way..

Any Ideas??

jparsons5-Sep-02 12:38

jparsons

5-Sep-02 12:38

I think your problem here is that the call to Receive won't return unless some data is present. So if you have multiple clients connected and only one of them is sending data, this will block on clients that are not sending data.

You must do one of several methods to determine if the Socket currently has data. The best ways are Polling and making the Socket nonblocking.

Jared
jparsons@jparsons.org
www.prism.gatech.edu/~gte477n

Re: CSocket new-b question

anju5-Sep-02 18:45

anju

5-Sep-02 18:45

Hi,what i call to you
first you register to codeproject and strength the family,

ok, r u tried with OnReceive fucntion?
u can search with "CHATSRVR" in MSDN .The article name
is "Demonstrates a Windows Sockets Server"
very nice programm,u can use this without CArchive class also'

anju

Anonymous5-Sep-02 12:05

5-Sep-02 12:05

Hey, I have a COM/ATL dll that I created for automating word. I have another application, written in C, that I need to open MS Word and load my dll. I know how to do all of this, but I am having a problem registering my dll. I currently do this:

//register the dll <br />
WinExec("regsvr32 /s WordAddin.dll", SW_SHOWNORMAL);<br />
rc = RegOpenKeyExHKEY_LOCAL_MACHINE, "SOFTWARE\\Microsoft\\Office\\Word\\Addins\\Word.Addin", 0, KEY_ALL_ACCESS, &hKey);<br />
<br />
if(rc != ERROR_SUCCESS)<br />
{<br />
WinExec("regsvr32 /s /u WordAddin.dll", SW_SHOWNORMAL);<br />
WinExec("regsvr32 /s WordAddin.dll", SW_SHOWNORMAL);<br />
}

At the end of my processing, I am unregistering the dll. It seems to work part of the time. The problem is that every once in a while, I click the button to launch MS Word from w/in my application but the dll is not getting registered. When I go out and manually look in the registry, it is not in the there. I have no idea why it is not registering the dll. Can anyone help or give me some insight into why this is happening and how I can fix it? I have looked and there are LOTS of posts about registering dlls and from what I could tell, I am doing it correctly. But something is wrong and I do not know what. It happens sporadically. PLEASE HELP!!!!!

Joaquín M López Muñoz5-Sep-02 12:20

Joaquín M López Muñoz

5-Sep-02 12:20

WinExec("regsvr32 /s ... //line 1
rc = RegOpenKeyEx(HKEY_LOCAL_MACHINE, ... // line 2

I'm far for sure about whant I'm going to say, but anyway: maybe the problem lies in the fact that WinExec works asynchronously, so by the time line 2 is reached it is possible that sometimes regsvr32 has not completed. In such cases, the last part of the code (which seems to me like a retry, am I right?) executes: again the lack of synchronicity can lead (in unlikely situations) to a wrong sequence of installations and uninstallations. If my guess is right, the problem shoul disappear by either:

Inserting generous Sleeps after all WinExecs (not an elegant solution).
Using CreateProcess instead of WinExec, which provides means for your program to wait till regsvr32 terminates before proceeding with the following step.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Anonymous5-Sep-02 12:29

5-Sep-02 12:29

You are correct, I am doing the check on the regisry with the hopes of retrying if the first attempt failed. I did initially try the CreateProcess but I kept getting a GPF when my program would reach the createprocess code. So I went with this code instead. The unable to register was happening before I put the RegOpenKeyEx call in though. It seems to run through the code, it just doesn't register the dll. Any thoughts on the CreateProcess, what I might need to do that I wasn't doing before? Can you give me a code snippet of what you think it should be? I appreciate any and all help you have and/or will provide!!!!

Joaquín M López Muñoz5-Sep-02 12:41

Joaquín M López Muñoz

5-Sep-02 12:41

Here's a sketch of how CreateProcess can be used:

  STARTUPINFO si;
  ZeroMemory(&si,sizeof(STARTUPINFO));
  si.cb=sizeof(STARTUPINFO);
 
  PROCESS_INFORMATION pi;
 
  if(!CreateProcess(
       NULL,
       (LPSTR)"regsvr32 /s WordAddin.dll",
       NULL,
       NULL,
       FALSE,
       DETACHED_PROCESS,   
       NULL,
       NULL,
       &si,
       &pi)){
    // handle error
  }
 
  WaitForSingleObject(pi.hProcess,INFINITE);
 
  DWORD dwExitCode;
  GetExitCodeProcess(pi.hProcess,&dwExitCode); // return code of the regsvr32
 
  CloseHandle(pi.hProcess);
  CloseHandle(pi.hThread);

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Anonymous5-Sep-02 13:24

Re: Creating Custom Control

5-Sep-02 13:24

Hey, THANKS!!!!!

I used the snippet and it did differ slightly from my original attempt. Sure enough, after using the CreateProcess, I have not had a problem with it not registering the dll. YOU RULE!!!

Creating Custom Control

MightyThor5-Sep-02 11:15

MightyThor

5-Sep-02 11:15

Hi,

I've read the two articles on this site "Creating Custom Controls" and "The Art Of Subclassing" by Chirs Maunder. They're pretty nice but i'm still confused.

Now, i want to build a custom control derived from CWnd.
As far as i understood, if we want to initialize something we use OnPaint function. Is that right?

And how do we add other controls to our control? For example, i want to build some kind of a table and i want column headers drawn on initialization. How and where should i do that?

And finally can you recommend me other tutorials about creating custom controls?

I'm really confused here, any bit of help is highly appreciated. Thanks.

Roger Allen6-Sep-02 2:06

Roger Allen

6-Sep-02 2:06

Declare a class inheriting directly from CWnd. Put the initialisation code in the Create() member. You should also create any child windows at this point. FOr example, you mentioned column headers.

To do that you would declare a member varaible of type CHeaderCtrl in the .h file and call Create on it in the Create() of your Cwnd derived class. You would also need to add code to the OnSize of you CWnd class to place the headre control in the correct place on the CWnd's main window. When it comes to drawing the control you put your drawing code i nyour OnPaint() and make sure you don't overwrite areas taken up by the child controls.

Roger Allen
Sonork 100.10016

I think I need a new quote, I am on the prowl, so look out for a soft cute furry looking animal, which is really a Hippo in disguise. Its probably me.

Re: Creating Custom Control

MightyThor7-Sep-02 9:14

MightyThor

7-Sep-02 9:14

Thanks for your reply. Now i have a starting point and thinks will sink better as i go the way.

CTree, change selection on right click

brianwelsch5-Sep-02 11:02

brianwelsch

5-Sep-02 11:02

When I right click on my tree, I would like to change the selection before displaying the context menu. Just like the behaviour in the class view window of VS.

How do I achieve this?
Confused | :confused:

It's probably obvious, and just can't see it.
Thanks,

BW
{insert witty/thought-provoking saying here}

Re: CTree, change selection on right click

Tomasz Sowinski5-Sep-02 11:13

Tomasz Sowinski

5-Sep-02 11:13

::GetMessagePos, CTreeCtrl::ScreenToClient, CTreeCtrl::HitTest and CTreeCtrl::SelectItem.

Tomasz Sowinski -- http://www.shooltz.com

** Putt knot yore thrust inn spel chequers. **

Re: CTree, change selection on right click

brianwelsch5-Sep-02 16:04

brianwelsch

5-Sep-02 16:04

BW
{insert witty/thought-provoking saying here}

Visual C++ book

marekm5-Sep-02 10:45

marekm

5-Sep-02 10:45

I'm interested in windows programming and I was looking for some books but I don't know wich one to buy. Do you have any suggestions?

marekm

brianwelsch5-Sep-02 10:53

brianwelsch

5-Sep-02 10:53

If your interested in MFC, then I'd recommend "Windows Programming with MFC" by Jeff Prosise. It's helped me out, along with the help I've gotten out here.

Good Luck!

BW
{insert witty/thought-provoking saying here}

adamUK5-Sep-02 12:31

adamUK

5-Sep-02 12:31

Second that... Jeff's book is great. Smile | :)

Also Sams 'teach yourself c++ in 21 days is quite good'. There's no Windows stuff in it which is great because it sidetracks you from learning the theory.

"I spent a lot of my money on booze, birds and fast cars. The rest I just squandered"
George Best.

valikac5-Sep-02 15:32

valikac

5-Sep-02 15:32

Do you want to learn MFC or Win32 API?

For MFC, I highly recommend that you study from these two books in the exact order listed.

Introduction to MFC Programming with Visual C++ by Richard M. Jones
Programming Windows With MFC by Jeff Prosise

For Win32 API, Programming Windows, The Definitive Guide to the Win32 API by Charles Petzold is unparalleled.

Kuphryn