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I have requiremnt where someone is passing me pointer to a buffer and I have to return value converted to that bufffer. I'm worried about buffer overrun. Here are two functions available for this..
_itoa(int value,char *buffer,size_t, int radix);
_itoa_s(int value,char *buffer,size_t, sizeInCharacters,int radix);
Here is my current function :
DWORD GetMessageSize(char *FileName, char *Size){
int intsize;
// do operation on file and get intsize
_itoa(intsize,Size,10);
return 0;
}
Since I don't know the size of buffer and if I use _itoa_s then how do I handle "sizeInCharacters" ?
Any help appreciated.
thanks
thanks
-- modified at 17:14 Tuesday 16th January, 2007
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when you pass buffers as functions parameters, you usually pass a couple of arguments : the buffer address (thru the pointer) and the buffer size...
here, the function is definitely not well designed.
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bs1977 wrote: Since I don't know the size of buffer and if I use _itoa_s then how do I handle "sizeInCharacters" ?
Short answer - you cannot use _itoa_s(...) correctly or in good faith without knowing the amount of valid buffer space you are passing telling it to use. toxcct's response is the correct way to handle this problem, if you want to use _itoa_s(...), otherwise switch to the plain old itoa(...) function.
Note that if you decide to change the function to accept the buffer size and you ever need to use Unicode or TCHAR code, be sure not to confuse the BYTE size of a buffer with its character size (sizeof( char ) == sizeof( BYTE ), but sizeof( wchar_t ) != sizeof( BYTE ) ).
Peace!
-=- James Please rate this message - let me know if I helped or not!<HR>If you think it costs a lot to do it right, just wait until you find out how much it costs to do it wrong!
Avoid driving a vehicle taller than you and remember that Professional Driver on Closed Course does not mean your Dumb Ass on a Public Road!
See DeleteFXPFiles
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Hello,
I am new to Win32API programming, Now is there a program that is available that will hook onto my program and basically tell me what messages are going into the message queue. It does not have to tell me all the messages but basic ones like WM_PAINT, WM_MOUSEMOVE, WM_LBUTTONDOWN, WM_LBUTTONUP, etc.
Thanks
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It sounds like you want Spy++.
"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15
"Judge not by the eye but by the heart." - Native American Proverb
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My problem is that i have a timer that querys data via ethernet, once this data is returned, it populates some fields displayed on my dialog. BUT i want to have an if statement in there such that if the user is editing/has focus of a edit box, i dont want to overwrite what has been changed. At first look, i figured it would be easy, and just check to see if it has focus, but for some reason GetFocus() returns NULL... Any ideas on why its return this? Im using the standard MFC timing, e.g. SetTimer( UINT nID, UINT millisec, UINT Func_ptr/*i think, or something like that. I use NULL here*/ )
"There are 10 types of people, those who understand binary, and those who don't."
- Somebody, not me.
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I'm not sure why you'd get NULL for GetFocus(). I thought a regular timer would be notified
on the same thread as the window proc but maybe not. The only thing I can think of is GetFocus()
is being called on a different thread than the window was created on.
An alternative would be to track focus on the associated edit controls by watching the
EN_SETFOCUS/EN_KILLFOCUS notification messages.
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Wait, i had an epihany... I'm sorry, the reason it is 0, is cause it IS a different thread... I forgot that my timer just sends a message, and i have a constant listener which handles all messages... Which means of course it returns 0... Thanks for the initial thought, sorry for the bother
"There are 10 types of people, those who understand binary, and those who don't."
- Somebody, not me.
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ok this might sound a little n00bish of me, but im desperate.
does anyone know how to create a .exe, that when loaded, launches 2 other exes.
and when the launching exe closes, the 2 exes it opened close too.
if any of you could provide me with some sample source or anything, i would be forever greatfull.
thank you.
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homerjaylol wrote: does anyone know how to create a .exe, that when loaded, launches 2 other exes.
Such as calling CreateProcess() twice?
"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15
"Judge not by the eye but by the heart." - Native American Proverb
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this answers the first part of the question (starting other exes)
the second part intends to close the programs previously started (in step 1) if our program shuts down
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toxcct wrote: this answers the first part of the question (starting other exes)
Which is all I intended to answer, hence the quoted text.
"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15
"Judge not by the eye but by the heart." - Native American Proverb
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DavidCrow wrote: Which is all I intended to answer, hence the quoted text.
oh,  hehehe, my bad David. 
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DavidCrow's suggestion works for launching the two applications. You can then get their handles, and you can keep checking the handles to see if either one (or both) of the child apps have closed.
To implement the close the other two when I close functionality, you can create a Named Event object, and signal it when the launching (parent) application starts to shutdown. The two child apps can check that event to see when they should shut down, and the parent app can check the child app's handles to know when they have shutdown and it can then complete its shutdown (or terminate the child app if it gets hung up and does not close on its own).
Peace!
-=- James Please rate this message - let me know if I helped or not!<HR>If you think it costs a lot to do it right, just wait until you find out how much it costs to do it wrong!
Avoid driving a vehicle taller than you and remember that Professional Driver on Closed Course does not mean your Dumb Ass on a Public Road!
See DeleteFXPFiles
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If you use CreateProcess to start the other apps, you can do this froim the OnClose override in CMainFrame...
SendMessage(m_hWndTelemetry, WM_CLOSE, 0, 0);
CloseHandle(processInfo.hProcess);
CloseHandle(processInfo.hThread);
"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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Closing the handles as shown will not cause the applications to shut down, so I am not sure that this was your intent, it simply releases the calling/parent app's "reference" to them, same as how closing a thread handle does not cause that thread to die immediately.
I do not believe that your suggestion will allow the calling app to ensure that the child apps have closed - they can ignore the WM_CLOSE message, or otherwise return from handling it and still be running.
Actually waiting for the handles to become signaled tells you when the apps have shut down (or, after a certain timeout, that they have not).
--- Edit: OK - you may have been specifically talking about how to cause the other two applications to initiate shutdown, as opposed to my suggestion of using an Event. Yes, that works as well, and is a bit simplier, but it should be mentioned that this only works for applications/processes that have a window and are pumping messages. And you still have to get the window handles for those child processes.
Peace!
-=- James Please rate this message - let me know if I helped or not!<HR>If you think it costs a lot to do it right, just wait until you find out how much it costs to do it wrong!
Avoid driving a vehicle taller than you and remember that Professional Driver on Closed Course does not mean your Dumb Ass on a Public Road!
See DeleteFXPFiles
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I'm getting closer to MFC each day 
I have now got into the habit of using thunks whenever a callback may be required within one of my classes. My code works perfectly, but only on Intel 32bit machines. I have placed exclusion guards around my template to prevent compiling for anything other than said machine, but now is the time to do it correctly.
This is my thunk:
struct THUNK
{
m_mov = 0xB9;
m_this = obj;
m_jmp = 0xE9;
m_relproc = Cast<char*>(proc) - Cast<char*>(this) - sizeof(THUNK);
}
This allows me to thunk without casting the hWnd paramaters. What would the equivlent be for a 64bit machine?
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Not knowing that much about thunks anymore, my first guess would be to account for the pointer size and structure layout/padding differences (this goes from 32-bit to 64-bit, and the size of the structure may now lie on a different boundary), but other than that, nothing that I can think of.
But I am no expert in the field of thunks... :P
Peace!
-=- James Please rate this message - let me know if I helped or not!<HR>If you think it costs a lot to do it right, just wait until you find out how much it costs to do it wrong!
Avoid driving a vehicle taller than you and remember that Professional Driver on Closed Course does not mean your Dumb Ass on a Public Road!
See DeleteFXPFiles
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Hi,
I am a bit curious.. Can I raise exception (with RaiseException()?)
and get it handled in another thread??
This is needed for operation stop-functionality.
I thought it would be nice to have one dialog
where is stop button, and it stops whatever the
main thread is doing..
Does anybody know how it is done in Visual Studio?
It's possible to freeze the debugged process anytime,
when debugging.
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I do not think that the exception will cross threads. I would suggest using a Win32 Event object, because it can be seen by multiple threads, and signal it in one thread to indicate the other to stop processing.
Peace!
-=- James Please rate this message - let me know if I helped or not!<HR>If you think it costs a lot to do it right, just wait until you find out how much it costs to do it wrong!
Avoid driving a vehicle taller than you and remember that Professional Driver on Closed Course does not mean your Dumb Ass on a Public Road!
See DeleteFXPFiles
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chilituna wrote: I thought it would be nice to have one dialog
where is stop button, and it stops whatever the
main thread is doing..
Is the dialog modal?
"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15
"Judge not by the eye but by the heart." - Native American Proverb
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chilituna wrote:
Can I raise Exception in one thread and handle it in another?
No, the handler has to be somewhere in the throwing thread's call stack.
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Hi, again a question about me with my IOCP skills 
ok, the situation is the following, everything works perfectly except for 1 thing, a really weird thing if you ask me.
I'm currently testing so i use 1 WorkerThread with 1 udp virtual connection at the time.
When i do a WSARecvFrom, i should recieve a buffer with a size of lets say 600 bytes. This hapends idd but later, here is my thing:
GetQueuedCompletionStatus(...)<br />
DWORD ioSize = 0;<br />
case RequestSend:<br />
break;<br />
case AfterSend:<br />
ioSize = static_cast<DWORD>(lpOverlapped->InternalHigh);<br />
break;<br />
case AfterRecieve:<br />
ioSize = static_cast<DWORD>(lpOverlapped->InternalHigh);<br />
This is the things i do, now it happends that in AfterRecieve, ioSize is the same as the size when i sended. better said, the data aint recieved yet, however i do get a notification that the data is recieved. When i put a breakpoint at that point, i see that the data is deliverd, to pull a conclusion, I get a notification when the data is recieved well it isnt untill i put a breakpoint at that place, really weird
weird story so:
dwIoSize = static_cast<DWORD>(ptrOverlapped->InternalHigh);<br />
ptrSession->incRecvBytes(dwIoSize);<br />
if ((iTemp = ptrGameClass->UnpackServerInfo(ptrSession->getNDServer(), &objToolset)) == 0){
pThis->FinishGame(ptrSession->getNDServer());<br />
__REPORT("SUCCEEDED");<br />
}<br />
else if (iTemp < 0){<br />
__REPORT("%s->UnpackServerInfo() failed", ptrGameClass->Gamename());<br />
}
To make it even more clear, whenever i put a breakpoint at: ptrSession->incRecvBytes(dwIoSize);, dwIoSize is 8 as the send buffer, but ptrOverlapped->InternalHigh is like 600 bytes.
When i do reports, it just reports that ptrOverlapped->InternalHigh is 8
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Hi,
I want to use the Code Snippets in Visual C++ VS2005 Professional.
But it seems it's not exist here.
When I go menu Tools\Code Snippets Manager I can not select a C++ from the "Language" combo box.
Is there some way to activate the Code Snippets stuff in C++, or it's available in another editions of Visual Studio 2005(for example VS2005 Developer Edition)?
Thanks.
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