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To write data to a serial port, you provide tha address of a buffer and the size of data to transmit. So if you want to send your DWORD, you simply need to do this:
DWORD dwMydata = 61118792;
WriteFile(...., &dwMyData, sizeof(DWORD), ....);
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how to write a merge sort program using COM?
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How it is related to COM ? COM is not a language. Have search on internet for same ?
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meet_kirankumar wrote: how to write a merge sort
Here[^] is an example.
meet_kirankumar wrote: using COM
Write a MergeSort function or class then call it.
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Hi,
I need to change the background color of a CStaic control to white color.
How can i do this ?
Thanks.
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Handle WM_CTLCOLOR
HBRUSH CMyDlg::OnCtlColor(CDC* pDC, CWnd* pWnd, UINT nCtlColor)
{
HBRUSH hbr = CDialog::OnCtlColor(pDC, pWnd, nCtlColor);
if(nCtlColor==CTLCOLOR_STATIC)
{
pDC->SetBkColor(RGB(255,255,255));
}
return hbr;
}
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Hi,
I tried this. But that is not changing all pixels of CStatic window. This changes only the text background color of CStatic window.
I need to change the color of whole CStatic window.
Thanks.
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You said in your OP, you want change background color of CStatic.
Try this code,
HBRUSH CMyDlg::OnCtlColor(CDC* pDC, CWnd* pWnd, UINT nCtlColor)
{
HBRUSH hbr = CDialog::OnCtlColor(pDC, pWnd, nCtlColor);
if(nCtlColor==CTLCOLOR_STATIC)
{
pDC->SetBkMode(TRANSPARENT);
hbr = CreateSolidBrush(RGB(255,255,255));
}
return hbr;
}
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C an any body tell me how 2 create frames in VC++ with buttons in detail prosedure.
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Are asking this with respect to MFC or SDK?
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Hi, I have a dialog box which has vertical scroll style enabled. The problem is, when i pull the scroll button down the controls in the dialog box move down. But when i pull the scroll button up the controls does not move up. The code which i have used is listed below
void CMyPropertyDlg::OnVScroll(UINT nSBCode, UINT nPos, CScrollBar *pScrollBar)
{
// TODO: Add your message handler code here and/or call default
CDialog::OnVScroll(nSBCode, nPos, pScrollBar);
SetScrollPos( SB_VERT , nPos , TRUE ) ;
ScrollWindow( 0 , GetScrollPos( SB_VERT ) ) ;
}
please help
-- modified at 0:03 Friday 23rd February, 2007
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The second parameter for ScrollWindow, yAmount must be a negative value to scroll up.
My idea is to take a member var which stores the previous pos, compare to see the direction and write code accordingly.
HTH,
Murali Krishna
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Hi all, this is my first message. i want to configure system timer for say 1msec exact, how to achive the perfact timing requirement in VC++, i have to transmit some message at every 1msec, at serial port. can anyone suggest how to do this.
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Your link is broken.
"Why don't you tie a kerosene-soaked rag around your ankles so the ants won't climb up and eat your candy ass..." - Dale Earnhardt, 1997
-----
"...the staggering layers of obscenity in your statement make it a work of art on so many levels." - Jason Jystad, 10/26/2001
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shriram_ch wrote: i have to transmit some message at every 1msec, at serial port
I'm almost positive that you can't possibly send discreet messages this fast, especially over a COM port. Your control code will need time to execute, and we're talking at least 3ms just to iterate the loop and send the message.
shriram_ch wrote: i want to configure system timer for say 1msec exact, how to achive the perfact timing requirement in VC++
Since the Sleep() function doesn't have that kind of granularity (depending on the platform, the best you can get out of it is about 25ms), you're going to need a higher-resolution timer.
There are a couple of articles here on CP that talk about high resolution timers.
http://www.codeproject.com/cpp/precisetimer.asp[^]
http://www.codeproject.com/datetime/perftimer.asp[^]
"Why don't you tie a kerosene-soaked rag around your ankles so the ants won't climb up and eat your candy ass..." - Dale Earnhardt, 1997
-----
"...the staggering layers of obscenity in your statement make it a work of art on so many levels." - Jason Jystad, 10/26/2001
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You probably won't be able to get 1ms regardless of what you use in Windows - it's not a RTOS.
You may want to look at the Waitable Timer API:
http://msdn2.microsoft.com/en-us/library/ms687012.aspx[^]
e.g.
- Create a watiable timer:
HANDLE TimerHnd = CreateWaitableTimer(NULL, FALSE, NULL);
- Create a job thread
- start loop
- WaitForSingleObject(TimerHnd, INFINITE);
- send message on serial port
- continue loop
- Set the waitable timer
SetWaitableTimer(TimerHnd, &due, 1, NULL, NULL, FALSE);
...
- Kill timer: (due = 0)
SetWaitableTimer(TimerHnd, &due, 0, NULL, NULL, FALSE);
CancelWaitableTimer(TimerHnd);
- Tell thread to exit, wait for it to exit
- CloseHandle(TimerHnd);
...cmk
Save the whales - collect the whole set
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Hi,
I am using Winsock(only TCP) and I wondered when a client really connects to a server. With connecting I mean the whole process of establishing a TCP connection (that means Handshake, and so on). Is this done via the connect(...) function or is it every time done when the client sends data to the server by the send(...) function?
The background of my question is, that I have a client app and I make a call to the connect() function when I initialize the client app. Now the user can choose between different actions, which asks the server for some data. That means, that there is only data send when the user chooses one of this actions; actually he can do nothing all the time. Is the way I do it okay, or would it be better to connect only to the server when the user chooses a specific action and then disconnect again (doing this then for every action)?
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With the TCP protocol, the connection is made once - during the connect() call.
You could connect for every transaction or keep a connection open. Whatever suits your needs
best.
Connecting every transaction adds the slight overhead (bandwidt/CPU) of establishing/closing the
connection. Web browsers do alot of that 
Mark
"Do you know what it's like to fall in the mud and get kicked... in the head... with an iron boot?
Of course you don't, no one does. It never happens. It's a dumb question... skip it."
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Hmm yes I thought of something like this...
But this yields in my next question: How can I disconnect from a server? I think there doesn't exist a command like disconnect(). So how is the best way to do this?
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FreeCastle wrote: I think there doesn't exist a command like disconnect()
They hide that information in the documentation[^] 
led mike
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Yes I know closesocket(), but I thought that there might be a better way, because when I call closesocket() then I also have to create the socket again, before calling the connect function.
But anyway thank you both.
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You're welcome (from led mike)
FreeCastle wrote: because when I call closesocket() then I also have to create the socket again, before calling the connect function.
That is part of the overhead of using that method.
I recommend:
Also follow led mike's link into Graceful Shutdown, Linger Options, and Socket Closure[^] for more general info.
Then check out DisconnectEx[^] for disconnecting a socket and reusing it (on XP+).
Cheers,
Mark
"Do you know what it's like to fall in the mud and get kicked... in the head... with an iron boot?
Of course you don't, no one does. It never happens. It's a dumb question... skip it."
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Ah thank you a lot, the first link was very informative.
That DisconnectEx function looks cute, but I think I'll avoid it because it only runs on XP or higher. I think I use shutdown, and if I understood that article right, I have also to "create" the socket (by a call to socket(...)) again, when I want to "reuse" it for a new connection.
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