C / C++ / MFC Discussion Boards

Re: What infected the exe ?

Todd Smith5-Jan-02 9:50

Todd Smith

5-Jan-02 9:50

What if it's a smart virii that modifies the checksum field?

Todd Smith

Re: What infected the exe ?

Michael Dunn5-Jan-02 10:00

Michael Dunn

5-Jan-02 10:00

A virus that analyzes the host program, locates the checksumming algorithm, runs it against itself, and saves & verifies a new checksum? Not likely. Wink | ;)

--Mike--
My really out-of-date homepage
Buffy's on. Gotta go, bye!
Sonork - 100.10414 AcidHelm
Big fan of Alyson Hannigan.

Re: What infected the exe ?

Mustafa Demirhan5-Jan-02 14:56

Mustafa Demirhan

5-Jan-02 14:56

Well, what if the target application is a crack program. Then it would be very very easy to crack the program. Poke tongue | ;-P

I think Colin is trying to protect an application from the crackers. If so, you should choose a third-party library. Here is a good one.http://www.bit-arts.com/ It is really expensive, but if you use ChargeKey service to sell your software, they provide these programs for free. Have a look at it.

Kind regards
Mustafa Demirhan

http://www.macroangel.com

Sonork ID 100.9935:zoltrix

sybase procedure to be called from vc++

Anusha4-Jan-02 18:05

Anusha

4-Jan-02 18:05

I have a procedure in sybase which has to be executed
in frontend thru VC++...So, how do u go abt it...! Right now i
have used DBGrid Control to access my info in the frontend...as per my understanding...!Or is there any other way to spool the info of the stored procedure....?I just have to see the data in the stored procedure ,excuted in the front end...!

plz help Frown | :(

Variable address issues

Stew4-Jan-02 16:12

Stew

4-Jan-02 16:12

I re-worked one of my functions today and for some reason, all of the new variables that I create share the same address and, therefore, share the same data. It's causing some issues with the handling of the application and I've never seen anything like this before. Does anyone have any ideas as to how this could happen or how I could fix it?

Re: Variable address issues

Philip Patrick5-Jan-02 0:17

Philip Patrick

5-Jan-02 0:17

Post the code here, so someone will answer more correctly.
It is something in your code, check assignments. Also are this variables pointers or not?
IS, post the code here Smile | :)

Philip Patrick
"Two beer or not two beer?" (Shakesbeer)
Web-site: www.saintopatrick.com

Re: Variable address issues

Stew5-Jan-02 6:40

Stew

5-Jan-02 6:40

Here is the code:

CString OffensiveBackfield;

if (true)
{
int ItemIndex;
CString Subheading;
CString SubheadingNumber;
bool SubheadingAdded = false;

//Populate the dialog item drop down lists with the position names
NumFormations = pApp->GetProfileInt("Offensive Backfield Formations\\Formations", "NumFormations", 0);
if (NumFormations > 0)
{
for (int j = 3; j < 6; j++)
{
for (i = 1; i <= NumFormations; i++)
{
_itoa( i, buffer, 10 );
FormationRegName = pApp->GetProfileString("Offensive Backfield Formations\\Formations", "Formation" + (CString)buffer);
NumReceivers = pApp->GetProfileInt("Offensive Backfield Formations\\Formations", "WR" + (CString)buffer, 0);
if (NumReceivers == j)
{
if (!SubheadingAdded)
{
_itoa(j, SubheadingNumber.GetBuffer(0), 10);
strcat(SubheadingNumber.GetBuffer(0), " Wide Receivers");
Subheading = SubheadingNumber;
ItemIndex = pOffensiveBackfieldBox->AddString(Subheading);
pOffensiveBackfieldBox->SetItemData(ItemIndex, 0);
SubheadingAdded = true;
}
TildeCheck = FormationRegName.Find(" ~ ");
if (TildeCheck != -1)
{
FormationName = FormationRegName.Left(TildeCheck);
}
else
{
FormationName = FormationRegName;
}
ItemIndex = pOffensiveBackfieldBox->AddString(FormationName);
pOffensiveBackfieldBox->SetItemData(ItemIndex, 1);
}
}
SubheadingAdded = false;
}
}
}
if(OffensiveBackfield != "")
{
pOffensiveBackfieldBox->SelectString(0, OffensiveBackfield);
}

For some reason, the variables "Subheading", "SubheadingNumber", and "OffensiveBackfield" all have the same address associated with them. After the line "_itoa(j, SubheadingNumber.GetBuffer(0), 10);", all three of the variables have the same data in them. This is not how it should be and I'm wondering how this is happening.

Re: Variable address issues

Michael Dunn5-Jan-02 6:58

Michael Dunn

5-Jan-02 6:58

Stew wrote:
_itoa(j, SubheadingNumber.GetBuffer(0), 10);
strcat(SubheadingNumber.GetBuffer(0), " Wide Receivers");

You have two problems there. First, you're allocating a buffer of length 0, so the _itoa() and strcat() calls are overrunning the buffer. Second, you're not calling ReleaseBuffer(). Do something like:

LPTSTR pszBuff = SubheadingNumber.GetBuffer(16);  // use a size big enough to hold the largest number you expect to have
 
  _itoa ( j, pszBuff, 10 );
  SubheadingNumber.ReleaseBuffer();  // return control of the char buffer to the CString
  SubheadingNumber += _T(" Wide Receivers");

--Mike--
My really out-of-date homepage
Buffy's on. Gotta go, bye!
Sonork - 100.10414 AcidHelm
Big fan of Alyson Hannigan.

Re: Variable address issues

Philip Patrick5-Jan-02 9:11

Philip Patrick

5-Jan-02 9:11

Oh, I'm late, LMAO, Well, Michael told ya already Smile | :)

Philip Patrick
"Two beer or not two beer?" (Shakesbeer)
Web-site: www.saintopatrick.com

help

DanYELL4-Jan-02 13:51

DanYELL

4-Jan-02 13:51

Can someone help me with a demo project? I have two (2) edit boxes. When I type something in one edit box I want the other edit box to instantaneously update. However, if I keep typing information, new information is typed on top of old information. It looks awful. I tried

m_edit0 = name;

GetDlgItem(IDC_EDIT0)->Invalidate();
GetDlgItem(IDC_EDIT0)->UpdateWindow();

and alot of other things, but nothing makes it work correctly. Please, please, can I email a demo project that illustrates this error and hopefully, someone will be able to help me fix it?

My email address is brinasas@yahoo.com

Sincerely,
Danielle (an overworked graduate student)

Re: help

Eugene Pustovoyt4-Jan-02 18:26

Eugene Pustovoyt

4-Jan-02 18:26

Hi Danielle,

Just try follows:

GetDlgItem(IDC_EDIT0)->RedrawWindow();

Should help!

Best regards,
Eugene Pustovoyt

Smile | :)

Sonork ID 100.10002:Yaumen

grrr ComboBox design-time item adding problem

Kuniva4-Jan-02 12:13

Kuniva

4-Jan-02 12:13

I have a ComboBox on my Dialog. I want to put items in it that aren't supposed to change so i open its properties and i type in the items seperated by CTRL+RETURN which takes me to the next line. For some reason the items dont show in the ComboBox when i run the dialog. (the dialog is called from another dialog with DoModal() ).

Can anyone think of a reason why the items wont show???? (i tried all different combinations of the properties, i tried changing the style and Owner draw and everything else so its not that)

Kuniva
--------------------------------------------
God gave man a penis and a brain but not enough blood to make both of 'em work at the same time.

Re: grrr ComboBox design-time item adding problem

Philip Patrick5-Jan-02 0:25

Philip Patrick

5-Jan-02 0:25

Maybe you are calling ResetContent() somewhere in your OnInitDialog()? Smile | :)

Philip Patrick
"Two beer or not two beer?" (Shakesbeer)
Web-site: www.saintopatrick.com

Accessing Interface of OCX...

Tim Rymer4-Jan-02 9:58

Tim Rymer

4-Jan-02 9:58

How do I access a MFC ActiveX .OCX interface in VC that was created in VC?

Thanks in advance...

~Timothy T. Rymer

www.digipen.edu
tim.xpertz.com

Re: Accessing Interface of OCX...

Philip Patrick5-Jan-02 0:31

Philip Patrick

5-Jan-02 0:31

Assuming that CLSID_ISomeInterface is the class id of interface you want to access, so the code of getting it should be like this:

ISomeInterface* pInterface = NULL;
CoCreateInstance(CLSID_ISomeInterface, NULL, CLSCTX_INPROC_SERVER,
                 IID_ISomeInterface, (void**)&pInterface );

the pInterface will contain your interface.
But the code can be different for different ActiveXs. If you want to know exactly, tell what interface you want to access.
Smile | :)

Philip Patrick
"Two beer or not two beer?" (Shakesbeer)
Web-site: www.saintopatrick.com

Blocking calls in worker thread

Jacob L. Anawalt4-Jan-02 9:02

Jacob L. Anawalt

4-Jan-02 9:02

I am trying to write a simple dialog based multi-threaded app that has a worker thread doing blocking socket reads from a non windows server (no serialization) and updating progress controlls on the dialog window (like an ftp app).

I first tried following the MFC examples, deriving my thread class from CWinThread. This runs, but doesn't work correctly. Windows messages, like scrolling, are blocked at times to all applications (not just my app). I tried setting the thread priority to the lowest, but still had problems with blocking. I guessed this was due to the thread being derived from CWinThread and having message maps, but unfortunatly the VC help files I found only talked about making worker threads from functions.

I searched and found a CThread class here on codeproject.com, and I switched my code over, deriving my worker class from the CThread class and eliminating the message maps for my worker thread (which I guess was realy a UI thread). Still the problem presents itself.

Any pointers to a multi-threaded application that updates a user interface with status progress while doing blocking work with another thread, or any other suggestions would be greatly appreciated.

Re: Blocking calls in worker thread

Anders Molin4-Jan-02 9:42

Anders Molin

4-Jan-02 9:42

Take a look at _beginthreadex() in MSDN, I always use it for creating threads. I really hate those thread-classes...

If you want to update a progressbar, from the thread, you can pass a pointer to the progressbar, to the thread, using the "void *arglist" parameter.

Then you can access the progressbar from your thread.

If you need to access the progressbar, at the same time, from the main thread, you can make some easy syncronizing using a Critical Section...

- Anders

Money talks, but all mine ever says is "Goodbye!"

Re: Blocking calls in worker thread

Jacob L. Anawalt4-Jan-02 12:07

Jacob L. Anawalt

4-Jan-02 12:07

I can give switching _beginthreadex() a try, and would be more willing to with some examples of using that to start a class instead of a function, but before I try, do you think that will help my problem? Will that make my blocking calls in the worker thread not affect the rest of the system?

I am not even sure if the blocking calls are the problem, or if it is due to the thread working so hard and using all cpu (as I stated before, I have tried the lowest thread priority with the same results). My mouse never has a problem moving, but waiting for a response to mouse clicks, scroll bar moves, etc on any app that is running, including my own and the windows task bar sometimes take a long time to respond.

Let me explain that better. While the transfer is happening, for about half of the time the computer is very responsive. The other half of the time it can be a few seconds or longer before the system responds. It jumps between the two states of responsiveness without any apparent pattern. Sometimes it will be very response although the worker thread is transferring a lot of data. Othertimes it will be unresponsive during the same condition.

As for updating a progress meter, origionaly I accessed the progress controll directly. My worker thread class has a member that points to it's owner thread -- the dialog. I was accessing the dialog's progress controll CProgressControll directly that way. By doing that, or even just having TRACE messages everywhere I would normaly step the progress bar, caused the system to crash after a partial 'download', and never at the same place. It was like I was sending too many messages for it (1.4Ghz) to keep up with.

Currently I have the worker thread update members on the owner thread, and an OnTimer on the owner thread/dialog to update the progress bars. That works better, the system doesn't crash and when messages are getting through the status update happens.

Has anyone seen a code example for something like an ftp transfer in a worker thread class using blocking winsock, with smooth and accurate status updates in a dialog thread class?

Re: Blocking calls in worker thread

Anders Molin5-Jan-02 4:11

Anders Molin

5-Jan-02 4:11

Jacob Anawalt wrote:
Will that make my blocking calls in the worker thread not affect the rest of the system?

I have never seen blocking calls effect the whole system, at least not if the thread have a low priority.

Are you running Win9x or NT/2k/XP?

Jacob Anawalt wrote:
While the transfer is happening, for about half of the time the computer is very responsive. The other half of the time it can be a few seconds or longer before the system responds. It jumps between the two states of responsiveness without any apparent pattern. Sometimes it will be very response although the worker thread is transferring a lot of data. Othertimes it will be unresponsive during the same condition.

I have no idea why this is happening, I have never seen anything like that. But, I always use NT/Win2k, and they handle threads a lot better that Win9x systems...

Another option would be to move away from the blocking socket, and use a async socket instead...

- Anders

Money talks, but all mine ever says is "Goodbye!"

Media Player

Jon Newman4-Jan-02 8:16

Jon Newman

4-Jan-02 8:16

Is there any freeware libraries for a media player (MP3, MPEG, AVI etc...) that does not need windows media player installed on the clients computer. Something like a third party dll containing MP3 decoder stuff. It will be used as an extra 'bonus' part of another program so it doesnt have to be too complex!
Ive already looked at the Audio/Video section of codeproject and nothing will do the job.
Any thoughts? Confused | :confused:

.NET or not .NET? MFC is the question......

Re: Media Player

Christian Graus4-Jan-02 11:19

Christian Graus

4-Jan-02 11:19

Oddly enough the sample that exists on CP is under an example for skinable apps. But there is full source here somewhere for playing mp3s, it's just used in the context of an app that is skanable, like Winamp.

Christian

I have come to clean zee pooollll. - Michael Martin Dec 30, 2001

Sonork ID 100.10002:MeanManOzI live in Bob's HungOut now

Re: Media Player

Stephen Caldwell4-Jan-02 11:39

Stephen Caldwell

4-Jan-02 11:39

There are lots of free decoder libraries, check out sites like www.sourceforge.net

Stephen Caldwell
Blackfission, CEO
http://blackfission.myip.org:81

Why "Failed to create the empty document"?

4-Jan-02 7:06

I use installshield for microsoft vc++6.0 to make a install programe. No error during setup, but when run the application program,it appear the warning dialog "Failed to create the empty document" in chinese -- i have a chinese version windows 98 in my computer. But it can run correctly in a PC installed VC++6.0. Can you tell me why? How can i solve this mistake? if it's because some dll files failed to install in the system , how can i find which dll file should i install?
thanks
zhaohanqing Cry | :((

Zhao hanqing

Re: Why "Failed to create the empty document"?

Philip Patrick5-Jan-02 0:34

Philip Patrick

5-Jan-02 0:34

Check the versions of MFC..dlls on the computer with no VS. This can cause a problem

Philip Patrick
"Two beer or not two beer?" (Shakesbeer)
Web-site: www.saintopatrick.com

How to enumerate all thread handles?

Stephen Kellett4-Jan-02 6:58

Stephen Kellett

4-Jan-02 6:58

Does anyone know how to get a list of all the thread handles in a process on Windows NT4.0? On Windows 2000 and Windows XP the toolhelp32 api can be used, but this is not available on Windows NT 4.0.

Also the process status helper library (PSAPI) has a function to enumerate all processes, but not all threads.

Note, I am interested in the thread handles, not the thread ids as I don't know of a way to get a thread handle if you know a thread id (that works on Windows NT 4.0).

Cheers

Stephen Kellett
--
C++/Java/Win NT/Unix variants
Memory leaks/corruptions/performance/system problems. UK based.
Problems with RSI/WRULD? Contact me for advice.

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