C / C++ / MFC

sudhir_Kumar11-Jul-08 19:52

sudhir_Kumar

11-Jul-08 19:52

Are the 5 Clients are instances of same client EXE.

-@SuDhIrKuMaR@-

Sameerkumar Namdeo11-Jul-08 20:05

Sameerkumar Namdeo

11-Jul-08 20:05

No. They can be of different application.

sudhir_Kumar11-Jul-08 20:55

sudhir_Kumar

11-Jul-08 20:55

If they are different applications then you can use WM_COPYDATA.It is very easy to use.

-@SuDhIrKuMaR@-

URLDownloadToCacheFile problem - possible workarounds?

Bram van Kampen12-Jul-08 14:35

Bram van Kampen

12-Jul-08 14:35

I have written software with your requirements, except that it could run on multiple networked machines. The approach I took was Named Pipes. I wrote a Generic Server, and a Generic Client, and, in effect, an RPC Procedure. In effect a 'SendMessage' procedure on the Client side, which gathered and wrapped all the Calling Info, created a Header, indicating where in the package each item resides, and, send it over the pipe. On the Server Side, you wait for the message, unwrap it, and present it to the function. For this to work, I created a MessageMap type of structure. For it to work better, Server and Client had only the Basic Bones in the Message Map for initial communication. At startup of the Client, it sends it's message map to the server, which the server registers.
When you have this Generic Server/Client system written, you make each app both a server and a client. Be sure though to make plenty of use of Synchronisation Objects.

N.B. The efford is always substantial, whatever route you take. I took this way because:
1. I considered RPC an overkill, and yet something else I had to learn and which Bill Gates could change on a whim.
2. Fully Debuggable, Very Few System calls you cannot debug into

Regards Smile | :)

Regards,

Bram van Kampen

x87Bliss11-Jul-08 11:11

x87Bliss

11-Jul-08 11:11

My program needs to download a file off the internet to get some information needed to continue. It does not need to save the information, just needs to read it once for the next step.

I have tried

CString TempFile;
URLDownloadToCacheFile(NULL, _T("http://validurl/script.cfm?key=value"), TempFile.GetBufferSetLength(MAX_PATH), MAX_PATH, validcallback);

Once those lines run, TempFile gets filled with a valid path to a temporary file, but the file doesn't actually exist - therefore I can't open it. The following code is what I'm using now, and it works. But I don't like it because it has a hard-coded temporary filename (therefore multiple instances may conflict).

CString TempFile;
TempFile.GetEnvironmentVariable(_(T"TEMP"));
TempFile.Appened(_T("\\MyProg.tmp"));
URLDownloadToFile(NULL, _T("sameurlasabove"), TempFile, validcallback);

After those lines run, the file is created and contains the needed information. But again, it uses a hardcoded temp file, therefore multiple instances cannot run.

So now for the questions:
First of all, is URLDownloadToCacheFile failing because it's a text file generated by a script, and not a binary data file (like a jpg), therefore it doesn't cache it?

Second, what is more practical in this situation. Would you implement code to generate a "random" temporary filename that's not in use? Or should I write code that can read the file right off the internet without saving it to disk first? I don't want to shoot a fly with a cannon, but I'm not sure which is the cannon.

SECURITY_ATTRIBUTES in threading

emmmatty111-Jul-08 8:03

emmmatty1

11-Jul-08 8:03

"The security attributes for the handle to the new thread. These security attributes include an inheritance flag that determines whether the handle can be inherited by child processes."

Can any 1 help me understand this?

Re: SECURITY_ATTRIBUTES in threading

Peter Weyzen11-Jul-08 13:56

Peter Weyzen

11-Jul-08 13:56

Without context, I wasn't sure what you were talking about. Googling your statement, reveals that this is part of "CreateThread".

Is that what you are asking about?

It sounds like you can pass security rights to a thread and give it the same rights you have acquired somewhere else?

From: http://msdn.microsoft.com/en-us/library/ms682453(VS.85).aspx[^]

HANDLE WINAPI CreateThread(
__in_opt LPSECURITY_ATTRIBUTES lpThreadAttributes,
__in SIZE_T dwStackSize,
__in LPTHREAD_START_ROUTINE lpStartAddress,
__in_opt LPVOID lpParameter,
__in DWORD dwCreationFlags,
__out_opt LPDWORD lpThreadId
);

lpThreadAttributes [in, optional]
A pointer to a SECURITY_ATTRIBUTES structure that determines whether the returned handle can be inherited by child processes. If lpThreadAttributes is NULL, the handle cannot be inherited.

The lpSecurityDescriptor member of the structure specifies a security descriptor for the new thread. If lpThreadAttributes is NULL, the thread gets a default security descriptor. The ACLs in the default security descriptor for a thread come from the primary token of the creator.

Windows XP/2000: The ACLs in the default security descriptor for a thread come from the primary or impersonation token of the creator. This behavior changed with Windows XP SP2 and Windows Server 2003. For more information, see Remarks

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~<br />
Peter Weyzen<br />
Staff Engineer<br />
<a href="http://www.soonr.com">SoonR Inc -- PC Power delivered to your phone</a>

Re: SECURITY_ATTRIBUTES in threading

zildjohn0111-Jul-08 14:14

zildjohn01

11-Jul-08 14:14

just use NULL. if you don't understand that you don't need to worry about security. your threads will be fine

CCheckListBox in release mode, Windows XP in Windows classic theme

tsvdevteam11-Jul-08 5:31

tsvdevteam

11-Jul-08 5:31

Hi,

I'm a bit desperate... so I'll do the old Police thing ... S.O.S

We work on an application that has been up and running for several years now - MFC based, links with Stingray. Until recently, CCheckListBoxes worked nice and easy. A new version is about to be released and we just realized that these "@!*!# check listboxes were not displaying strings in release mode running on WindowsXP, when the display is in "Windows 2000 (classic)" theme. The string ARE there, we just can't see them.

In between versions we have split up our app into 4 dll's.. but I still don't get it, it's basically the same code....

Any help, idea or creative suggestion to commit suicide is very much welcome....

Thanks

PS. I built a small test dialog application, and it works. Seems to be a bit more complicated...

[OT] Re: CCheckListBox in release mode, Windows XP in Windows classic theme

David Crow11-Jul-08 6:08

David Crow

11-Jul-08 6:08

tsvdevteam wrote:
I'm a bit desperate... so I'll do the old Police thing ... S.O.S

But it needs to be in a bottle.

"Love people and use things, not love things and use people." - Unknown

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

Re: CCheckListBox in release mode, Windows XP in Windows classic theme

bob1697211-Jul-08 7:42

bob16972

11-Jul-08 7:42

I had that problem with plain Visual C++ 6.0 MFC apps. I tried various things and got numerous false positives. I finally gave up trying to use CCheckListBoxes with Visual C++ 6.0 and any app that needed them, I moved to Visual C++ 2003.

I'm not sure if that helps but I thought I'd pass on the fact that I fought the good fight for a reasonable amount of time but never found that magic fix that worked on 2000, XP, Vista, Theming enabled/disabled etc...

Re: CCheckListBox in release mode, Windows XP in Windows classic theme

tsvdevteam11-Jul-08 9:03

tsvdevteam

11-Jul-08 9:03

Well, that is fine for the source code I write myself. I did write a class to avoid using the faulty one. But, Stingray (Roguewave) uses the bad class in their customize toolbar dialog. I could mess with their source code, but I'd like to avoid doing so.

Thank you for the info !

Re: CCheckListBox in release mode, Windows XP in Windows classic theme

Bram van Kampen12-Jul-08 14:47

Bram van Kampen

12-Jul-08 14:47

That explains it All
I was just wondering what Stingray was about to do to your code\n
Advice: Before you throw a party for fellow students, LOCK UP YOUR COMPUTER

WTF | :WTF:

Regards

Bram van Kampen

Update only a particial area of a View with UpdateAllViews(...)

CrocodileBuck11-Jul-08 4:55

Re: Update only a particial area of a View with UpdateAllViews(...)

11-Jul-08 4:55

Hi,

i want to update only a part of a view with UpdateAllViews().
I read that the simpliest way is to call UpdateAllViews() from the doc and pass a CRect to the view's OnUpdate().
The rect which is passed to the view's OnUpdate() ist the part which is updated.

But it wont work Cry | :((

, I tried it for some hours now, could you helpme? Confused | :confused:

Perhaps you know a tut which covers this problem i only found the simple UpdateAllViews(NULL)samples ?

Here is some source from me which updates the whole view doc.cpp:

CString CMyDoc::LoadFile(CString cstrSearchString, CString *ptrArrFileNames, CString cstrFileExtension, int iZaehler)
{
	m_iZaehler = iZaehler;
	ptrMlf->loadmyfile (cstrSearchString + m_ptrArrFileNames[iZaehler],cstrFileExtension);
	m_cstrText = ptrMlf->lf_cstrText;

	UpdateAllViews(NULL); // Calls OnUpdate of the view and updates the whole view !!!

	return m_cstrAusgabe;
}

Here the code from the view.cpp:

void CMyView::OnUpdate(CView* pSender, LPARAM lHint, CObject* pHint) 
{
	CTheReaderDoc	 *pDoc	= GetDocument ();
	CRichEditCtrl	 &rCtrl = GetRichEditCtrl();	
	rCtrl.SetWindowText (pDoc->m_cstrAusgabe);
	rCtrl.SetFont(pDoc->m_ptrFont);
	rCtrl.SetModify(TRUE);	
}

Many thanx & best regards
Wink | ;)

ShadowEater

Mark Salsbery11-Jul-08 5:05

Re: Update only a particial area of a View with UpdateAllViews(...)

11-Jul-08 5:05

UpdateAllViews() gives you TWO parameters that get passed to all the
CView::OnUpdate() calls.

What about passing a pointer to a CRect in one of those paramters?

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

led mike11-Jul-08 5:18

led mike

11-Jul-08 5:18

CrocodileBuck wrote:
I read that the simpliest way is to call UpdateAllViews() from the doc and pass a CRect to the view's OnUpdate().
The rect which is passed to the view's OnUpdate() ist the part which is updated.

But it wont work , I tried it for some hours now

The code you posted is not trying to use a CRect so how are we supposed to know what you are trying that is not working? Confused | :confused:

led mike

Re: Update only a particial area of a View with UpdateAllViews(...)

CrocodileBuck11-Jul-08 5:27

Re: Update only a particial area of a View with UpdateAllViews(...)

11-Jul-08 5:27

Thx for yor quick replies,

here the code which tries to pass a pointer to CRect:

Doc.cpp:

CString CMyDoc::LoadFile(CString cstrSearchString, CString *ptrArrFileNames, CString cstrFileExtension, int iZaehler)
{
	m_iZaehler = iZaehler;
	ptrMlf->loadmyfile (cstrSearchString + m_ptrArrFileNames[iZaehler],cstrFileExtension);
	m_cstrAusgabe = ptrMlf->lf_cstrAusgabe;

	CRect *MyRect;
	MyRect(100, 100, 100, 100);
	CObject* pHint = NULL;
	pHint = reinterpret_cast<cobject*>(MyRect);

	UpdateAllViews(NULL, 1, pHint);

	return m_cstrAusgabe;
}

Many many thanx and best regards
Croc

Mark Salsbery11-Jul-08 5:31

Re: Update only a particial area of a View with UpdateAllViews(...)

11-Jul-08 5:31

That code compiles?

Maybe try something simpler:

CRect MyRect(100, 100, 100, 100);
CObject* pHint = (CObject*)&MyRect;

UpdateAllViews(NULL, 1, pHint);

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

CrocodileBuck11-Jul-08 5:46

Re: Update only a particial area of a View with UpdateAllViews(...)

11-Jul-08 5:46

Thanx,

it will work, i could now pass the CRect!
Simple is Simply the best way Wink | ;)

But do you know what i have to do in the OnUpdate of the viw.cpp ?
The view will not automatically update only the rect area ?
I men when i print text in my view and then load new text my version of UpdateAllViews should only update the rect ???

But how?

Sorry for my stupid question Confused | :confused:

but i m really confused !

Many thanx
Croc

Mark Salsbery11-Jul-08 6:05

Re: Update only a particial area of a View with UpdateAllViews(...)

11-Jul-08 6:05

A simple call to InvalidateRect() in your OnUpdate() overrides should do it.

void CMyView::OnUpdate(CView* pSender, LPARAM /*lHint*/, CObject* pHint)
{
   InvalidateRect((CRect*)pHint, TRUE);
}

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

CrocodileBuck11-Jul-08 6:16

Re: Update only a particial area of a View with UpdateAllViews(...)

11-Jul-08 6:16

Hi Mr. Salsbery,

i tried

InvalidateRect((LPCRECT)pHint, TRUE);

but it won't work Frown | :(

Thanx for all your help
Croc

Mark Salsbery11-Jul-08 6:29

Re: Update only a particial area of a View with UpdateAllViews(...)

11-Jul-08 6:29

What does "won't work" mean?

If you're using a rect of (100,100,100,100) then nothing will
happen, since the rect has no dimensions (width and height are 0).

Try a valid rect! Smile | :)

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

CrocodileBuck11-Jul-08 6:33

Re: Update only a particial area of a View with UpdateAllViews(...)

11-Jul-08 6:33

Hi,
yes thats right but i tried it with

CRect MyRect(0,0, 200, 150);
CObject* pHint = (CObject*)&MyRect;

and this fails too!

Manx thanx and best regards
Croc

Mark Salsbery11-Jul-08 6:36

Re: Update only a particial area of a View with UpdateAllViews(...)

11-Jul-08 6:36

What does "fails" mean?

Doesn't compile? Crashes at runtime? Nothing happens?

It marks the area for updating. The next WM_PAINT message will
update that area. If the same exact data is drawn as on the last WM_PAINT,
you're not going to see a difference.

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

CrocodileBuck11-Jul-08 6:44