Re: Making an Application Hang. - C / C++ / MFC Discussion Boards

Re: how to insert data in sqlserver 2005 using vc++6.0

CPallini2-Nov-09 23:15

CPallini

2-Nov-09 23:15

eswar pothula wrote:
SQLExecDirect(hstmt,(unsigned char *)"insert into emp values(empnum,'ename',esal)",SQL_NTS);

That's wrong.
Try to change it to:

const int SIZE = 256;
char sqlcmd[SIZE];
sprintf(sqlcmd, "insert into emp values(%d,'%s',%f)", empnum, ename, esal);
SQLExecDirect(hstmt,(unsigned char *) sqlcmd, SQL_NTS);

of course, in real life, you should check for buffer overruns, etc...
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

Making an Application Hang.

Hari_162-Nov-09 22:52

Hari_16

2-Nov-09 22:52

Hi All,

I have a dialog based application and are there any general scenarios where i can make the application hang.

Thanks,
Hari

Re: Making an Application Hang.

CPallini2-Nov-09 22:57

CPallini

2-Nov-09 22:57

Hari_16 wrote:
I have a dialog based application and are there any general scenarios where i can make the application hang

There are quite a lot, I suppose.
Smile | :)

Re: Making an Application Hang.

Hari_162-Nov-09 23:01

Hari_16

2-Nov-09 23:01

Can u name some of them.....

Re: Making an Application Hang.

Adam Roderick J2-Nov-09 23:06

Adam Roderick J

2-Nov-09 23:06

Well it is difficult to point some, until and unless knowing your intentions Sniff | :^)

Величие не Бога может быть недооценена.

Re: Making an Application Hang.

Hari_162-Nov-09 23:12

Hari_16

2-Nov-09 23:12

Honestly .. no specific intentions just had some crashes and fixed it .. so was thinking of ways to hang an application .

In my project i use multithreading and critical section to synchronise them....

Re: Making an Application Hang.

Adam Roderick J2-Nov-09 23:47

Adam Roderick J

2-Nov-09 23:47

Multithreading and synchronization is not more than enough for a dead lock.
Smile | :)

Just check the the various conditions of dead lock.
have to home work on your operating system knowledge
Just refer Modern operating systems from Andrew S. Tanenbaum.
I love this book
Smile | :)

Величие не Бога может быть недооценена.

Re: Making an Application Hang.

Rajesh R Subramanian2-Nov-09 23:58

Rajesh R Subramanian

2-Nov-09 23:58

If you do not use a critical section, that won't make your application "hang". You'll possibly lose out on data corruption due to race condition, but the threads will continue to execute and at worst you'll take a nasty crash (like an access fault).

But a using or not using a critical section won't have anything to do with a "hang", unless a thread is being a dog and locking a resource (for a long time) that the UI thread is waiting for. But that boils down to my other reply that I've posted to your original query.

“Follow your bliss.” – Joseph Campbell

Re: Making an Application Hang. [modified]

CPallini2-Nov-09 23:17

CPallini

2-Nov-09 23:17

You may put an infinite loop somewhere.
Your thread may wait for a dead synchronization object.
A blocking I/O function call...
[added]
You may even lauch Eclipse, for the purpose
[/added]
There are quite a lot ways for you, to make it happen...
Smile | :)

modified on Tuesday, November 3, 2009 5:28 AM

Re: Making an Application Hang.

Hari_162-Nov-09 23:56

Hari_16

2-Nov-09 23:56

Thks a lot ....

Re: Making an Application Hang.

PrafullaShirke272-Nov-09 22:57

PrafullaShirke27

2-Nov-09 22:57

You want to construct or Destruct the application ? Big Grin | :-D

Re: Making an Application Hang.

Hari_162-Nov-09 22:59

Hari_16

2-Nov-09 22:59

At the moment Destruct Smile | :)

Re: Making an Application Hang.

Rajesh R Subramanian2-Nov-09 23:47

Rajesh R Subramanian

2-Nov-09 23:47

By "hang", I assume that an application becomes unresponsive? If that's it, then blocking the UI thread would be almost the only reason why it happens.

For example, if there's a lengthy calculation of some sort, like parsing a huge file, then that should be done on a separate thread.

“Follow your bliss.” – Joseph Campbell

Re: Making an Application Hang.

Hari_162-Nov-09 23:58

Hari_16

2-Nov-09 23:58

Thks for ur reply

Re: Making an Application Hang.

Randor 3-Nov-09 5:21

Randor

3-Nov-09 5:21

Hari_16 wrote:
where i can make the application hang

I am not sure why you want to hang your own thread but this should work:

SuspendThread(GetCurrentThread());

Best Wishes,
-David Delaune

Re: Making an Application Hang.

Hari_163-Nov-09 18:14

Hari_16

3-Nov-09 18:14

Thks it worked ......

Direct3D (DXUT) Problem

Ali Tavakol2-Nov-09 22:37

Ali Tavakol

2-Nov-09 22:37

Dear friends,
When I draw a simple cube, in a DXUT empty project (which can be found in DirectX Sample Browser), the cube becomes transparent. all sides of the cube are visible. I like to have a concrete cube. I'm exhausted. How can I do that?

Change background color of combo box's dropdown list.

Member 38346302-Nov-09 22:00

Member 3834630

2-Nov-09 22:00

Hello,
How to change the background color of the dropdown list in combo box.
I changed the back ground color of dialog box in OnCtlColor() method, this changed the color of all the items on the dialog.

I could individual controls color but not able to change the dropdown list color of combo box.

Below is the code snippet.
if(pWnd->GetDlgCtrlID() == IDC_COMBO1)
{
HBRUSH g_bkcolor = CreateSolidBrush(RGB(255,255,255));
pDC->SetTextColor(RGB(0,0,0));
pDC->SetBkColor (RGB(255,255,255));
hbr = g_bkcolor;
return hbr;
}

If someone knows how to change the color please let me know.. Thank You..

Re: Change background color of combo box's dropdown list.

PrafullaShirke272-Nov-09 22:30

PrafullaShirke27

2-Nov-09 22:30

1.Derive the Combo box class
2.Overide the WM_CREATE message
i.e CBS_OWNERDRAWFIXED in Create function
3. Handel the DrawItem function of Combobox
Here
a. Fill the Item's rectabgle with the color you wanted to show as background
b. Then drawtext on top of it.

I think this much clue is sufficient.

Re: Change background color of combo box's dropdown list.

Member 38346302-Nov-09 22:44

Member 3834630

2-Nov-09 22:44

Thanks for the reply.
I am not that expect in MFC to get it.
Could you explain it with an example?

Than you once again..

Re: Change background color of combo box's dropdown list.

PrafullaShirke272-Nov-09 22:55

PrafullaShirke27

2-Nov-09 22:55

Using colors in CEdit and CStatic[^]

This article will help you to understand how to create the custom control according to requirement. After understanding those start working on your combo box.

Not Recieving Message Notification

002comp2-Nov-09 21:42

002comp

2-Nov-09 21:42

Hello Friends
I am using setWindowLong with parameters like:

HWND colorpickerHwnd= bmap->GetWindow();
    WNDPROC wpOrigPPProc15 = (WNDPROC) SetWindowLong(colorpickerHwnd,
   GWL_WNDPROC, (LONG) PPSubclassProc15);

and the Window Procedure is

LRESULT CALLBACK  PPSubclassProc15(
    HWND hwnd, 
    UINT uMsg, 
    WPARAM wParam, 
    LPARAM lParam) 
{
	
	if(uMsg == WM_LBUTTONDOWN)
	{

        }
    return CallWindowProc(wpOrigPPProc15, hwnd, uMsg, 
        wParam, lParam);

}

Now,the Problem is that It is going to that Window procedure but not recieving any messages(like mouse click and move etc)
Am I missing Something?
please suggest me something.

Thanks
Yogesh

Re: Not Recieving Message Notification

Richard MacCutchan2-Nov-09 21:58

Richard MacCutchan

2-Nov-09 21:58

yogeshs wrote:
Now,the Problem is that It is going to that Window procedure but not recieving any messages(like mouse click and move etc)

This does not really make sense; if it is calling the windows procedure then it must be sending messages to it.

What is 'bmap' and where does it sit in the zorder of your windows? Are you sure it has the focus at the time that you are trying to use the mouse on it?

Re: Not Recieving Message Notification

002comp2-Nov-09 22:04

002comp

2-Nov-09 22:04

bmap is object of BitMap.
Actually I change from vs 2002 to vs 2008.In 2002 it was working but after conversion it is behaving like this.

Re: Not Recieving Message Notification

002comp2-Nov-09 22:35

002comp

2-Nov-09 22:35

As I think Problem in getting handle of BitMap.
Beacuse now we are getting like this:

Bitmap *bmap;
BitmapInfo* bi = new BitmapInfo(mybmt->GetMapName());
BMMRES stat;
bmap = TheManager->Load(bi, &stat);
bmap->Display("", BMM_CN, FALSE, TRUE);
colorpickerHwnd = bmap->GetWindow();

Now,whenever I click on border of that window only then it is going inside of WM_LBUTTONDOWN but when i click Inside of the Window means on Bitmap then No response.

Is any problem in getting handle to that Bitmap?
thanks

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