E_NOINTERFACE - C / C++ / MFC Discussion Boards

Re: typedef

George_George19-Feb-08 14:14

George_George

19-Feb-08 14:14

Thanks Rajkumar,

Both of them are correct. Smile | :)

regards,
George

Re: typedef

Rajkumar R18-Feb-08 22:24

Rajkumar R

18-Feb-08 22:24

George_George wrote:
it does not compile because const is qualified on (the whole) type int& not on the near one int, right?

his question,
rcInt ref = 0;
const int_ref_t x = 0;
both evaluates to a reading const int &x = 0; then how compiler interprets

Prasanth M V wrote:
U are getting error not beacuse of "const", but as it is reference variable.

how about rcInt ref = 0; it is also a reference variable.

how the error because of reference variable came here, because in the expression,
const int_ref_t x, const qualifier on reference type (int_ref_t) is ignored and x become the type int &. while compiler interprets rcInt ref = 0, as reference variable of type const int.

Re: typedef

Prasanth M V18-Feb-08 22:37

Prasanth M V

18-Feb-08 22:37

Hi Raj,

I understood from his question that whether "const int_ref_t x = 0; " became error.

int_ref_t x is equivalnet to int& x. Am i right?

Then it will end with error. Does my expalnation make sese??

Thanks
Prasanth M V

Re: typedef

Rajkumar R18-Feb-08 22:50

Rajkumar R

18-Feb-08 22:50

Prasanth M V wrote:
I understood from his question that whether "const int_ref_t x = 0; " became error.

No, its not "whether", he know there is a compilation error, his question is whether this is because const is qualified on ( int & ) type, while in the previous statement const is qualified on (int) of reference variable &x.

george_george wrote:
In the following segment, it does not compile because const is qualified on (the whole) type int& not on the near one int, right?

Prasanth M V wrote:
Does my expalnation make sese??

then what ur "NO" means, does he is not correct that const is qualified on type (int &)

Re: typedef

Prasanth M V18-Feb-08 23:46

Prasanth M V

18-Feb-08 23:46

OK.

Sorry if my statement milead you.
What i meant is that the error is beacause of reference variable, not by const.

Thanks
Prasanth M V

CRT Security and Gotcha

suhast18-Feb-08 20:24

suhast

18-Feb-08 20:24

We use VC++ 6.0 for many years, and now here is VC++ 2005 and comming or arived VC++ 2008. Now the main issue is, how to write your code which will run on VC++ 6.0 and VC ++ 2005, yes I mean the new CRT security features.
see the function that you need to write:
strcpy, wcscpy, mbscpy, _tcscpy, _tcscpy_s. Now, somebody will say that just disable the warning and go ahead. But my question is...

Is There any way that you can write the code which will run equally on VC 6.0 and 2005, I mean w/o much effort, do not ask me to write all that predefined macros, like #if VCPP2005 then this and then that?

Why can not compiler decide that this code is for 2005 and this is for the lower version?

Any good answer??? I mean to Chris Maunder.

Thanks.

Re: CRT Security and Gotcha

James R. Twine10-Mar-08 4:52

James R. Twine

10-Mar-08 4:52

IMHO, the best way to do this is to create #defines that kick in when you are building is VC++6.0 that point back to the older versions of the SDK functions.

For example:

#if _MSC_VER <= 1200
#define _tcscpy_s( D, BS, S )     _tcscpy( D, S );
#endif

   Something like that will work, but you may get warnings about unused parameters.

   This is not that hard to do, because you can find the include file that #defines the TCHAR-variants of the secure versions of the string handling functions and use it to make things easier.

   Peace!

-=- James
Please rate this message - let me know if I helped or not!<hr></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!
Remember that Professional Driver on Closed Course does not mean your Dumb Ass on a Public Road!
See DeleteFXPFiles

E_NOINTERFACE

john563218-Feb-08 19:59

john5632

18-Feb-08 19:59

Hi Experts,

I am trying to get the files and folders name from RecycleBin. But the statement "hr = m_pRecycleBin->CreateViewObject (m_hWnd, IID_IShellDetails, (VOID**)&pDetails);" is returning E_NOINTERFACE.

I could not know what is happening?

My code is:

<br />
CoInitialize(NULL);<br />
<br />
	HMODULE m_hShell32 = LoadLibrary(_T("SHELL32.DLL"));<br />
	typedef IShellFolder	FAR*	LPSHELLFOLDER;<br />
	typedef IShellFolder2	FAR*	PSHELLDETAILS;<br />
	LPSHELLFOLDER	m_pRecycleBin;<br />
	<br />
	<br />
<br />
	BOOL			bReturn			= FALSE;<br />
	STRRET			strRet;<br />
	LPMALLOC		pMalloc			= NULL;<br />
	LPSHELLFOLDER	pDesktop		= NULL;<br />
	LPITEMIDLIST	pidlRecycleBin	= NULL;<br />
	HRESULT			hr				= S_OK;<br />
	m_pRecycleBin=NULL;<br />
	SHGetMalloc(&pMalloc); // windows memory management pointer needed later<br />
	hr = SHGetDesktopFolder(&pDesktop);<br />
	hr = SHGetSpecialFolderLocation (m_hWnd, CSIDL_BITBUCKET, &pidlRecycleBin);<br />
	if (NULL != m_pRecycleBin)<br />
	{<br />
		m_pRecycleBin->Release ();<br />
		m_pRecycleBin = NULL;<br />
	}<br />
	hr = pDesktop->BindToObject(pidlRecycleBin, NULL, IID_IShellFolder, (LPVOID *)&m_pRecycleBin);<br />
	if (SUCCEEDED (hr))<br />
	{<br />
		bReturn = TRUE;<br />
	}<br />
	if (S_OK == pDesktop->GetDisplayNameOf (pidlRecycleBin, SHGDN_NORMAL, &strRet))<br />
	{<br />
		GetName (strRet);<br />
	}<br />
<br />
	pMalloc->Free (pidlRecycleBin);<br />
	pDesktop->Release();<br />
	pMalloc->Release();<br />
	//return bReturn;<br />
<br />
	PSHELLDETAILS pDetails = NULL;<br />
	//HRESULT hr = S_OK;<br />
<br />
	SHGetMalloc(&pMalloc); // windows memory management pointer needed later<br />
	hr = m_pRecycleBin->CreateViewObject (m_hWnd, IID_IShellDetails, (VOID**)&pDetails);<br />
	if (SUCCEEDED (hr))<br />
	{<br />
		TCHAR szTemp[MAX_PATH];<br />
		SHELLDETAILS sd;<br />
		int iSubItem = 0;<br />
<br />
		while (SUCCEEDED (hr))<br />
		{<br />
			hr = pDetails->GetDetailsOf (NULL , iSubItem, &sd);<br />
			if (SUCCEEDED (hr))<br />
			{<br />
				switch (sd.str.uType)<br />
				{<br />
				case STRRET_CSTR:<br />
					_tcscpy (szTemp, sd.str.cStr);<br />
					break;<br />
				case STRRET_OFFSET:<br />
					break;<br />
				case STRRET_WSTR:<br />
					WideCharToMultiByte (CP_ACP, 0, sd.str.pOleStr, -1, szTemp, sizeof (szTemp), NULL, NULL);<br />
					pMalloc->Free (sd.str.pOleStr);<br />
					break;<br />
				}<br />
				//m_List.InsertColumn (iSubItem , szTemp, LVCFMT_LEFT, 100);<br />
				iSubItem ++;<br />
			}<br />
		}<br />
	}<br />
	if (NULL != pDetails)<br />
	{<br />
		pMalloc->Free (pDetails);<br />
	}<br />
	pMalloc->Release();<br />
<br />

Re: E_NOINTERFACE

Rajkumar R18-Feb-08 20:16

Rajkumar R

18-Feb-08 20:16

pther wrote:

typedef IShellFolder2 FAR* PSHELLDETAILS;

...

PSHELLDETAILS pDetails = NULL;
hr = m_pRecycleBin->CreateViewObject (m_hWnd, IID_IShellDetails, (VOID**)&pDetails);

type is IShellFolder2 and query for IID_IShellDetails, although this is not the error, returning E_NOINTERFACE means the interface is not supported by the object,

looking into IShellDetails, gives the information, IShellDetails is superseeded by
IShellFolder2 in newer version of windows,

change to

hr = m_pRecycleBin->CreateViewObject (m_hWnd, IID_IShellFolder2, (VOID**)&pDetails);

that make sense to the type u defined

Re: E_NOINTERFACE

john563218-Feb-08 20:34

john5632

18-Feb-08 20:34

I tried with "hr = m_pRecycleBin->CreateViewObject (m_hWnd, IID_IShellFolder2, (VOID**)&pDetails);"

But problem is remain same.
It is also returning E_NOINTERFACE.

Question about Mutex and Atoms. [modified]

User 238229218-Feb-08 19:55

User 2382292

18-Feb-08 19:55

What is the "scope" of a mutex? (you know, when preventing multiple instances)

Is it "active" for multiple users?? i mean, lets say an app creates a Mutex to mark it's residency....if a second user executes an app...and it attempts to "OpenMutex()" is it successfull??

Also What's the Scope of Atoms??? (across multiple users)

offtopic : how long does it take for an article to be verfied by CP staff?

-st0le [st0le'n'stuff softwarez!]
http://st0lenc0des.googlepages.com/

modified on Tuesday, February 19, 2008 2:13 AM

modified 20-Oct-19 21:02pm.

Re: Question about Mutex and Atoms.

Iain Clarke, Warrior Programmer18-Feb-08 22:25

Iain Clarke, Warrior Programmer

18-Feb-08 22:25

I'm no huge expert, but I've just had a look at the documentation for CreateMutex...

Terminal Services: The name can have a "Global\" or "Local\" prefix to explicitly create the object in the global or session name space. The remainder of the name can contain any character except the backslash character (\). For more information, see Kernel Object Name Spaces. 

Windows XP: Fast user switching is implemented using Terminal Services sessions. The first user to log on uses session 0, the next user to log on uses session 1, and so on. Kernel object names must follow the guidelines outlined for Terminal Services so that applications can support multiple users.

So, I'd guess you need to put Global\ in front of a mutex name for the same one to be accessed (and there used) by differing processes from differing users.

If you look online for the documentation, I'm sure you can see how they work for Vista too - but I'd be surprised if it's different.

As for atoms? They're all around us, maaaaaaaan. (OK, I don't know, but I imagine it's in MSDN too)

OT: Mine took ~2 weeks, but that wasn't recent.

Iain.

Iain Clarke appearing in spite of being begged not to by ^CPallini.

import address table (IAT)

George_George18-Feb-08 19:32

George_George

18-Feb-08 19:32

Hello everyone,

1.

After my study, the address of IAT of an executable is known at compile/link time, other than known at load/runtime, right?

I have this confusion because if an EXE needs to link with an import library, some of the instructions in the import library contains pointers to the address to the IAT entries of the EXE (right?) which needs to be fixed-up during load time. So, if IAT address is not known at compile/link time, import library will not be able to contain pointers to the address of IAT.

2.

IAT address of an EXE is some default address which has the same values for all EXE?

thanks in advance,
George

Re: import address table (IAT) [modified]

User 238229218-Feb-08 19:43

User 2382292

18-Feb-08 19:43

So, if IAT address is not known at compile/link time, import library Lookup Table will not be able to contain pointers to the address of IAT.

Yes. That is true...but certain programs (like viruses,exe protected files) can "build" (or rather fill) their Import Table by themselves...The IAT is sometimes "purposely" corrupted ...it used to be some kind of anti-disassembly trick. (i doubt if it works anymore...)

IAT address of an EXE is some default address which has the same values for all EXE?

No, It does not have a fixed addr...You can grab the RVA (Relative Virtual Address) from the PE Header...For the Physical Address you'll need to convert RVA into Physical Address.

-st0le [st0le'n'stuff softwarez!]
http://st0lenc0des.googlepages.com/

modified on Tuesday, February 19, 2008 2:34 AM

modified 20-Oct-19 21:02pm.

Re: import address table (IAT)

George_George18-Feb-08 20:10

George_George

18-Feb-08 20:10

Thanks st0le,

My question is answered.

regards,
George

Registering an OCX

Chandrasekharan P18-Feb-08 18:59

Chandrasekharan P

18-Feb-08 18:59

I dont know if this is the right forum to post this message... if not please pardon me..

I need to register an OCX which i got from the net. used Regsvr32 to register it. but if failed to register. it was goveong me an error

something like this

DllRegisterServer c:\windows\myocx.ocx failed
return code was :0x80004005\

what needs to be done to register it?

thanks

Re: Registering an OCX

Rajesh R Subramanian18-Feb-08 19:18

Rajesh R Subramanian

18-Feb-08 19:18

Are you logged on as an administrator?

Nobody can give you wiser advice than yourself. - Cicero
.·´¯`·->Rajesh<-·´¯`·.
Codeproject.com: Visual C++ MVP

Re: Registering an OCX

Chandrasekharan P18-Feb-08 19:27

Chandrasekharan P

18-Feb-08 19:27

No. i guess i need to have admin rights to register an OCX.. right?

Thanks.. Guess the query is resolved

Re: Registering an OCX

Rajesh R Subramanian18-Feb-08 19:39

Rajesh R Subramanian

18-Feb-08 19:39

At first, you need to be an administrator or power user to register a component with DLLRegisterServer. But don't yet decide your query is resolved. It could have failed for other reasons too.

Nobody can give you wiser advice than yourself. - Cicero
.·´¯`·->Rajesh<-·´¯`·.
Codeproject.com: Visual C++ MVP

Re: Registering an OCX

Chandrasekharan P18-Feb-08 22:27

Chandrasekharan P

18-Feb-08 22:27

yes that was the reason. was not in administrator mode.. activex component successfully registered.

Error C2440 in VC++.

T.RATHA KRISHNAN18-Feb-08 18:57

T.RATHA KRISHNAN

18-Feb-08 18:57

I'm working in a VC++ project. I've received an error which states that

error C2440: 'static_cast' : cannot convert from 'void (__thiscall CPerspectiveView::* )(UINT,short,CPoint)' to 'BOOL (__thiscall CWnd::* )(UINT,short,CPoint).

When I double click on this error,the cursor goes to a Windows Message Map called ON_WM_MOUSEWHEEL(). I have checked the address of the function corresponding to this Message in both the files(i.e .cpp and .h).
They are the same only. Please help me to resolve this error.

Re: Error C2440 in VC++.

Rajkumar R18-Feb-08 19:04

Rajkumar R

18-Feb-08 19:04

i assume CPerspectiveView is your custom class derived indirectly from CWnd

the return type of the function corresponding to the message map should be BOOL.

change the return type of message handler for ON_WM_MOUSEWHEEL in the CPerspectiveView to BOOL;

Re: Error C2440 in VC++.

T.RATHA KRISHNAN18-Feb-08 19:26

T.RATHA KRISHNAN

18-Feb-08 19:26

Thank u. It's working.

Re: Error C2440 in VC++.

Chandrasekharan P18-Feb-08 19:12

Chandrasekharan P

18-Feb-08 19:12

the problem can be with the return type.. change the return value from void to BOOL. is should work.

Interface excel-sheet with MFC SDI application(.exe)

MuneesRaj18-Feb-08 18:20

MuneesRaj

18-Feb-08 18:20

I want to interface the Excel shheet with MFC SDI application.how will you do that ?

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.