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I'm writing a MFC program in Visual Studio 6.0. When I run it on my Windows XP cumputer it works great, but if I try it on my other computer with Windows 98 the program starts to "eat" memory at a very fast rate.
I have traced the problem to the following function (if I comment it out the program stops using up all the memory on the Windows 98 computer)
CClientDC dc(this);
CDC buffer;
buffer.CreateCompatibleDC(&dc);
CBitmap bitmap;
bitmap.CreateCompatibleBitmap(&dc, SKARM_BREDD, SKARM_HOJD);
buffer.SelectObject(&bitmap);
CBrush vit(RGB(255, 255, 255));
CRect rect(0, 0, SKARM_BREDD, SKARM_HOJD);
buffer.FillRect(&rect, &vit);
for(int i = 0; i < sidor.size(); i++)
{
buffer.MoveTo(skarmKoord.at(sidor.at(i).hornPunkter.at(0)));
for(int j = 1; j < sidor.at(i).hornPunkter.size(); j++)
buffer.LineTo(skarmKoord.at(sidor.at(i).hornPunkter.at(j)));
buffer.LineTo(skarmKoord.at(sidor.at(i).hornPunkter.at(0)));
}
dc.BitBlt(5, 5, SKARM_BREDD, SKARM_HOJD, &buffer, 0, 0, SRCCOPY);
Is it something wrong with this code?
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jonsson_84 wrote:
When I run it on my Windows XP cumputer it works great... with Windows 98 the program starts to "eat" memory...
How are you verifying these?
jonsson_84 wrote:
buffer.SelectObject(&bitmap);
Where is the call to restore the bitmap?
"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)
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Actually I don't know if Windows 98 is the problem. I can hear when Windows starts to swap memory to the hardsisk.
I don't restore the bitmap. Is that the problem? How do I restore it?
Update: I have tried it on one more Windows 98 computer now, the results are the same.
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jonsson_84 wrote:
I can hear when Windows starts to swap memory to the hardsisk.
Hardly a valid test, don't you think? While increased disk activity does indicate something is happening, without the proper tools in place, it would be really hard to pinpoint anything specific.
"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)
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Of course I know that many things can increase the disk activity but it "felt" like a memory leak and it seems like I was right.
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You must unselect bitmap from buffer, you are leaking GDI-resources.
Change:
CBitmap bitmap;
bitmap.CreateCompatibleBitmap(&dc, SKARM_BREDD, SKARM_HOJD);
buffer.SelectObject(&bitmap);
to
CBitmap bitmap;
bitmap.CreateCompatibleBitmap(&dc, SKARM_BREDD, SKARM_HOJD);
CBitmap* oldbitmap = buffer.SelectObject(&bitmap);
and add (after the BitBlt)
buffer.SelectObject( oldbitmap );
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It works now.
Thanks for the help!
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Hi all,
I am trying to allow users to configure their printers from a web page. I am thinking of referencing an activeX control inside my asp.net page to then allow user to configure their printers.
Requirements
I want the user to setup three different printing schemas (one for reports, one for receipts, etc.) . I also want these settings to be specific to the workstation and global for all users using the same configurations.
Is an ActiveX control available (third-party) or some code I could reference ?
Any advice appreciated.
(I didn't really no where this post fit in, so I put it here)
R.Bischoff
.NET, Kommst du mit?
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I am having trouble with linking files due to global class objects. What is the best way to define them and not having to use extern in other header files?
Will making a CPP file specifically for these global class objects work (I would try this myself but since my very long code is now cluttered and in need of re-writing I can't test it without spending a couple of days of re-writing)
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What do you mean by "global class objects?" Are you wanting an instance of a class that is accessible in more than one file? I would think that using the extern keyword would work best here. Do you have reservations about its use?
"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)
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Yes, that's exactly what I mean. I don't have a specific problem using it but I wanted to have one file where everything global is defined so I wouldn't have to go into every file and use extern in its header. Is this possible at all?
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yes, it is possible.
Here's one way :
#ifdef DECLARE_GLOBALS
#define Global
#else
#define Global extern
#endif
class CMyClass
{
...
};
Global CMyClass g_GlobalObject;
then place the definition :
#define DECLARE_GLOBALS
in one and ONLY one file, before it includes the header declaring CMyClass.
__________________________________________
a two cent stamp short of going postal.
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Use a common header file, with the extern keyword, that is included by every implementation file. For example, MFC uses 'stdafx.h' file to include all common Windows/MFC/Sockets/ODBC/Whatever header files required in all files.
Of course, you need to use a pragma definition (#pragma once), otherwise you might get multiple-declaration errors.
Always remember, though that having too many global objects is a sure way to invite trouble in the house. Put only those variables global that MUST be, use class members and pointers to class members elsewhere whenever possible. For example, if I have a dialog that has a list control, my database class might have a direct pointer to this control, allowing manipulation where necessary.
-Antti Keskinen
----------------------------------------------
The definition of impossible is strictly dependant
on what we think is possible.
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OK, this is something that I was thinking of. Let me try to understand this. Make a header file and include the global class objects as externs, then include this header file in every cpp file that needs to use those objects.
I don't understand the final step. Does it have to be clearly defined in one file as not extern? If so, is this where #pragma comes in?
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I generally find it problematic to put variable declarations (as opposed to definitions) into header files. The tricks suggested about using #ifdef... are really just to trick the compiler into accepting a generally ill-advised way of writing code.
My suggestion is to declare your global variables in the source file where they are originally created, not in a header file, and then every other source file that needs access to the global variables needs to use extern. For these other source files, they can #include a GlobalVars.h file that simply contains all of the necessary extern statements for the global variables. The main source file does not #include GlobalVars.h, as it is the file that is declaring them.
The advantage to this approach is that variables (and the access to them) is not hidden through a set of #include, #define, and #ifdef statements. You are writing exactly what you want in a straightforward way that will be less prone to error and easier to understand.
While it makes no difference to the compiler, it will be more understandable to anyone reading the code.
Dave
"You can say that again." -- Dept. of Redundancy Dept.
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I am trying to write a small program in VC++7 (win32 console app) that invokes BIOS and DOS interrupts. I am taking an assembly langiage class, and I can add __asm blocks, but the program crashes whenever int 10h, int21h or int 33h is called. Apparently VC7 does not support the int86 function for calling interupts. Can anyone help with this
'
James Meade
vLT(jg) vUSN
vOPSOFF VAQ-140
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If you're using Windows NT, Windows 2000, or Windows XP then using DOS interrupts directly are going to give you problems because those versions of Windows don't use DOS.
Jeremy Falcon
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Tank_Aviator wrote:
...but the program crashes whenever int 10h, int21h or int 33h is called
As it should. The HAL is doing its job by restricting access to the hardware. You'd need to create a ring-0 application if you want to communicate directly with the hardware. This article has some useful bits in it.
"The pointy end goes in the other man." - Antonio Banderas (Zorro, 1998)
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The BIOS and DOS ints don't exist inside a Win32 console app. You need to create a 16 bit DOS app with the 16 bit tools and then run that, which will mostly work on NT.
Paul
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You can't, use the correct Win32 APIs instead: for example, CreateFile for opening files, SetConsoleOutputCharacter and kin for manipulating the console.
Stability. What an interesting concept. -- Chris Maunder
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it does support them but you are not allowed to call interrupts except the general ones and the native interrupts for windows nt.
if you are calling anything different your software WILL crash!
even in kernel mode you don't have access to bios interrupts because the system uses it's own ways to communicate with the hardware. I propose you have a look at the future!
Don't try it, just do it! 
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This is an odd question to place in the correct forum, so I chose this one hoping it would be the most relavent due to the subject.
I have a bunch of VS.NET 2003 C++ projects that I need to compile in VC++ 6.0. Don't ask why because it pains me just to think about it. The projects will all compile fine with VC6 so that wont be a problem. I could recreate the project files by hand, but it would take me a good few days to do them all and even after doing just one my nerves are a complete mess. What I need is a utility, macro, or whatever that can take a VS.NET 2003 project file and create a VC6 one with the appropriate settings carried across (or one that can take VS.NET 2002 files as there is a converter between 2003 and 2002 on this site).
Does such a thing exist or am I destined to be punished and should stock up on caffeine?
Putting the laughter back into slaughter
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I think you are look for this[^].
Chris Meech
We're more like a hobbiest in a Home Depot drooling at all the shiny power tools, rather than a craftsman that makes the chair to an exacting level of comfort by measuring the customer's butt. Marc Clifton
VB is like a toolbox, in the hands of a craftsman, you can end up with some amazing stuff, but without the skills to use it right you end up with Homer Simpson's attempt at building a barbeque or his attempt at a Spice rack. Michael P. Butler
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So much for the CodeProject search. 
Thanks Chris. ![Beer | [beer]](https://codeproject.global.ssl.fastly.net/script/Forums/Images/beer.gif) ++
Putting the laughter back into slaughter
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Hi. I have a question: how can I change the pixel values of a jpeg image? (after decompression of course). I'm not really good at this... any help is appreciated. Thanks.
We are accidents waiting to happen...
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