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You can not mix and match new/delete with malloc/free/realloc. Just because version of the compiler implemented it using malloc means that the same will work for a different version.
The standard specifically states that delete can only be used with new.
Tim Smith
I'm going to patent thought. I have yet to see any prior art.
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Although the current compiler you are using calls malloc as part of its implementation of the new-handler, this is not specified by the C++ standard, and should not be relied on. Another compiler (or a more recent version of the compiler) can change the implementation so that malloc is not called. The result from calling realloc on a buffer allocated with new is undefined. While it may work with this version of the compiler when allocating a POD, it is not a good practice to rely upon an implementation detail that you have no control over. If you decide that realloc is the only way to go, don't use new for the original allocation - just use malloc.
You should be able to use a vector anywhere that you use a raw allocated buffer. What are you trying to do that you don't think will work with a vector?
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Hi,
Looks like I'm having a brain fart this morning and can't remember how to cancel the closing of a property sheet.
I have two property pages, and I validate some settings in the CMyPropPage1::OnOk() handler. If the settings are invalid, I display a msgbox to the user and want to leave the property sheet displayed. However, it's closing after the user closes the msgbox! When the settings are invalid, I simply return from the handler (which appears to be wrong...). So, what do I have to do to keep it displayed??
Thanks!
Chris
"No one goes to hell because of their sin, but because of rejecting God's method of salvation: His Son's life for yours..."
"It does not take a majority to prevail ... but rather an irate, tireless minority, keen on setting brushfires of freedom in the minds of men." --Samuel Adams
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Well when OnOK is called in the PropertySheet all the PropertyPageses that have been activated get their OnOK called. That means all the pages have been validated; therefor, no matter what the return is from OnOK on the Sheet it will close. Al least that is my experiance. It may be totally incorrect but it is what I tell myself to feel better. 
So what do you do? In all my PropertySheets I validate at the Page level. That way if a page fails then I show message and return there.
Hope it helps.
***********************
Tony Fontenot
Recreational Solutions
tony@recsolutions.com
***********************
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I'm writing an application with heavy mt.
the app runs for about 20 seconds, and then crashes in a malloc call, either through new or CString operator <<
I HAVE used the mt runtime, and it doesn't help.
the linker complained about libc conflicts, so I exluded it with /NODEFAULTLIB
Is it dangerous to load an mfc dll, from an atl application?
Anyone with a hint?
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No. But it is dangerous to have buggy code that trashes memory causing malloc to break.
You software is buggy. Look for buffer overruns or accessing memory that has been freed.
Tim Smith
I'm going to patent thought. I have yet to see any prior art.
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Would I be unreasable if I said You where rude?
Just assuming my "buggy" code being a reason, seems - to me - like a habit of writing bad code. (?)
If you have nothing better to write...
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No, he was not rude, he was right.
Don't take it personally: everyone writes buggy code. Good professionals find bugs and fix them before shipping to users.
And take his advice, it's not easy to write thread safe code, the number of race conditions in the simplest code is impressive and a buffer overrun is easy.
Just a sample: try doing a strcat on two threads at the same time and you'll have a buffer overrun.
Your incessant rantings indicate you have a brain the size of a pea, and the mental capacity of a bag of hammers. - John Simmons
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Well, I was being a little rude. But time and time again I see people blame malloc or some other silly thing for their own bugs.
I always look at the compiler/library last as the source of my problems. In 15 years, I think I have found only 4 compiler/library bugs. The 999,985 other bugs were all my fault. And even that number is probably a gross under-estimation.
Tim Smith
I'm going to patent thought. I have yet to see any prior art.
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Tim Smith wrote:
But time and time again I see people blame malloc or some other silly thing for their own bugs.
The same people that never post a code sample demonstrating the bug.
I know what you feel like, I had a really BIG discussion (may I call it fight?) with a fellow programmer that insisted he wouldn't even look at his code, because the bug was in the COM+ thread pool. "The proof? Use the component as a non-pooled component and everything works ok".
Well, looking 5 minutes at his code I found the bug.
Your incessant rantings indicate you have a brain the size of a pea, and the mental capacity of a bag of hammers. - John Simmons
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I have always had the philosophy that between my code and the compiler, only my code can be modified. So there is little point looking at the compiler. Even in the VERY rare case of a compiler problem, your only choice is to modify your code to avoid the problem. :/
Tim Smith
I'm going to patent thought. I have yet to see any prior art.
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Well, I have to admit that I was childish, and appoligize.
I have to eat my pride, and present this subtle bug:
<br />
static void OptimizeAllocSize(DWORD* cLength)<br />
{<br />
static const int nGranularity = 512;<br />
*cLength = (((*cLength)/nGranularity))*nGranularity;<br />
}<br />
one warner to any buffer class: (MSC)
<br />
_ASSERTE(!m_pBuffer || ( *(LPDWORD)((LPBYTE)m_pBuffer-4)==0xFDFDFDFD ) && ( *(LPDWORD)((LPBYTE)m_pBuffer+m_dwCapacity)==0xFDFDFDFD ));<br />
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The thing is that the question was that could it be the non multihtreaded application libraries that caused these errors.
As far as I know - malloc isn't thread safe in the single threaded library, so I thaught that because the linker complained about compatibility between the stdlib, st-malloc could be my problem. Now my code was buggy, and is now fixed. Shame on me.
Thanks for your constructive comment.
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I have problem with socket functions.
Does anyone know what I am doing wrong?
I tried simple client (SMTP)
TCP/IP (SOCK_STREAM)
how program looks:
m_hSocket = socket(... //OK
connect(m_hSocket... //OK
send(m_hSocket... //OK
recv(m_hSocket... //OK
send(m_hSocket... //still OK
recv(m_hSocket... //error !!!!!
What's the problem:
I am conected.
I can send my request.
I can read answer.
I can send another request,
but I am not able to read answer.
There is some error.
( WSAGetLastError return zero ??)
How I can keep connection?
Thank you
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The other side of the connection closed the request.
Make sure that you have a supporting reciprocator, sometimes your peer will close the connection and thats something you should detect. Remember, SMTP is not a connection based protocal, but connectionless in the sense that you don't maintain a TCP connection with the server.
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Hello, please help me!
I want to allow a User to resize an EditControl in my SDI - Application at runtime.
I create a CEdit control with editcontrol.create(........)
when I use the Style WS_THICKFRAME all is correct and I can handle the Message WM_NCMOUSEMOVE, but I have an ugly border around my EditBox.
When I create a CEdit Box without WS_THICKFRAME no WM_NC... message is sent to my box.
How can I manage that a WM_NC... message is send to box without using WM_THICKFRAME.
(I dont know how to use WM_NCCALCSIZE)
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Hi,
I am sending data to a dB which represents monetary values. And am using the Period (.) as the decimal symbol. But notice that the values entered into the dB vary depending on the Regional settings and the decimal symbol selected.
How do I obtain what the current settings are?
Or how does one solve the problem?
Thanks in advance
Rui
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GetLocaleInfo gives you this kind of information in it's rawest form.
Depending on how you're talking to the DB (ODBC, OLE DB, DAO) it's normally avoidable, unless you're actually submitting raw SQL requests yourself.
Steve S
[This signature space available for rent]
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I am trying to determine the best way to dynamically display text in a docking control bar.
I have a VC++ MFC application that is continually sent text from a separate process. I need to display this text on a multi window UI. I would like to provide a number of docking windows on the display and display the text in these windows.
I have implemented a test application by deriving my own class from CDialogBar and creating a CClientDC object to display the text in my docking Dialog Bar window.
Is this the best way to achieve my desired result?
Secondly I want to have a scroll bar on my docking control bar window so I can scroll the displayed text. So far I have not been able to create a scroll bar on a Control Bar window.
What is the best way to achieve this?
Any suggestions on the above to points would be greatly appreciated.
Thanks,
David
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DavidH wrote:
Is this the best way to achieve my desired result?
There are quite a few ways to achieve your result - the best one is the one that works for you. Sounds like you have a good start, perhaps simply creating an Edit control on your dialog bar would suffice (and take care of your scrollbar problem).
For a fancier solution, check out this:
http://www.datamekanix.com/[^]
Shog9
------
Rather hammer futiley at the locked door than just sit and ignore it. Obviously finding a way to get through the locked door would be even better though. - Paul Watson, My Ignorance
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Ok,
I hope someone can help. I have a small app written in C++ in Visual Studio 6 which has to to ported to C++ in Visual Studio .Net Everything comiles fine apart from the call to the HtmlHelp. The line of code in VS6 look likes this :
HtmlHelp(NULL, "unitshelp.chm::/Unit_Definitions_Dialog.htm", HH_DISPLAY_TOPIC, 0);
Now when this compiles in VS.Net it just says that HtmlHelp does not take 4 parameters. I can't find anything on MSDN that tells me how to display my HtmlHelp file. All it says is that HtmlHelp takes a DWORD_PTR and a UINT!!! My app contains all the necessary includes and libraries because it was working just fine when compiled in VS6. Any help greatfully received;)
Jeremy
___________________________
Jeremy Preston
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Hi dear,
How can I change a directory security programmatically?
Thank you in advance.
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:(I need to draw an icon using BitBlt function so to draw it within limited rectangle and I need the exact width and height of the icon. I noticed that if the icon is drawn using the standard colors, Ipicture.get_Width and Ipicture.get_Height will return the exact width and height of the icon, but if the icon is drawn using 265 colors, Ipicture.get_Width and Ipicture.get_Height will not return the correct values. What can I do to overcome this problem?
Julia
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Does anyone know a product (free or not) like a C++/MFC library, ActiveX control, etc. that is a mathematical equation editor? I also need a mathematical expression evaluator. My problem is that I have a set of equations that have to be input in an MFC application. For this, I need an equation editor. Then, I need to evaluate the equations in a certain order that is why I need the expression evaluator. I will appreciate any help you can give me.
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I've written a bunch of them. Currently I was working on one that would compile the expression into actual machine code so it would (hopefully) be able to evaluate the expressions faster (i.e, wouldn't have to traverse the parse tree each time). If you're interested, I might write an article on it.
Chris Richardson
Programmers find all sorts of ingenious ways to screw ourselves over. - Tim Smith
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