C / C++ / MFC

14-Jan-09 19:57

(I sorry to put the message isue the lounge) Frown | :(

i create a Service progam, and use it to WinExec a other progress,
now In this progress ,CFileDialog f.OpenFile.(as saveas)
but i cant get the Desktop,
the message is "you refers to a invalid Desktop Frown | :(

thanks

Naveen14-Jan-09 21:25

Naveen

14-Jan-09 21:25

Basically its not a good idea to interact with the desktop from a service. How ever I think giving the dektop interactive privilage to the service will solve your problem. To do so, select your service in the service constrol manager( "services.msc" ), take the logon tab, tick the "Allo&w service to interact with desktop" check box and restart your service.

ox0101 wrote:
create a Service progam, and use it to WinExec a other progress,

WinExec function should not be used by newer applications. Please use CreateProcess() or ShellExecuteEx() functions.

nave

[OpenedFileFinder] [My Blog]

Emilio Garavaglia14-Jan-09 21:42

Emilio Garavaglia

14-Jan-09 21:42

Thats due to the fact that a "desktop object" is associated to a user session with the OS, and that a service have no "destop" since it run inside the OS behind the users.
It is in general wrong to assume that a service is running inside a user context.
What you can do is try to get who are the user that are logged on the machine, get the desktop associated to one of them and then create the process into that context.

See MSDN about "Windows Stations", "Desktop Objects" and the "CreateProcess" API.
WinExec is not the good API, since it creates the new process in the same context of its creator (that has no place to have an interactive interface, being a service).

****
On more remind: to be more productive, don't title a post in a programming forum "Help me", since it gives no clue about the nature of the help.
Imagine the forum displaying 100 posts titled "help me". Do we have to open all of them before to understand if we can helpful or not ?
A more appropriate tile may be "Process and Services", for example.

2 bugs found.
> recompile ...
65534 bugs found.
D'Oh! | :doh:

ox010115-Jan-09 20:08

15-Jan-09 20:08

sorry,

i will give a nice title next time Smile | :)

«_Superman_»14-Jan-09 22:43

«_Superman_»

14-Jan-09 22:43

You can use the CreateProcessAsUser API to run the other program in the context of an interactive user.

«_Superman_»

KarstenK14-Jan-09 23:05

KarstenK

14-Jan-09 23:05

if you want to this, the service has to run under a user account. But this isnt right. A serivce hasnt anything to do on a desktop of a user. Use the "All User" Directories for output.

Greetings from Germany

ox010115-Jan-09 14:35

15-Jan-09 14:35

thank everyone,
sometimes i cant express my mind

the title is "CFileDialog in Windows Service"
i cant get the loged user's Desktop
Now i find a method,but it's my result i want to get
the fllowing:

PSID psidEveryone;
// Create a SID for the built-in "Everyone" group
SID_IDENTIFIER_AUTHORITY sidAuth = SECURITY_WORLD_SID_AUTHORITY;
if (!AllocateAndInitializeSid( &sidAuth, 1, SECURITY_WORLD_RID,
0, 0, 0, 0, 0, 0, 0, &psidEveryone )){
// Error
}

HWINSTA hWinSta = GetProcessWindowStation();
if (hWinSta == NULL){
// Error
}
AllowAccessToWinSta(psidEveryone,hWinSta);

HDESK hDesk = GetThreadDesktop(GetCurrentThreadId());
if (hDesk == NULL){
// Error
}
(from Jerry Richer 's Program Service-Side Windows)

ox010115-Jan-09 14:37

Moving dailog box by clicking anywhere not only on caption bar?

15-Jan-09 14:37

How Can use it?
i put it in my ON_BN_CLICK
example:(i still dont get the loged user's desktop )

PSID psidEveryone; <br />
<br />
			// Create a SID for the built-in "Everyone" group<br />
			SID_IDENTIFIER_AUTHORITY sidAuth = SECURITY_WORLD_SID_AUTHORITY;<br />
			if (!AllocateAndInitializeSid( &sidAuth, 1, SECURITY_WORLD_RID, <br />
			   0, 0, 0, 0, 0, 0, 0, &psidEveryone )){<br />
			   // Error<br />
			}<br />
<br />
			HWINSTA hWinSta = GetProcessWindowStation();<br />
			if (hWinSta == NULL){<br />
			   // Error<br />
			}<br />
			AllowAccessToWinSta(psidEveryone,hWinSta);<br />
<br />
			HDESK hDesk = GetThreadDesktop(GetCurrentThreadId());<br />
			if (hDesk == NULL){<br />
			   // Error<br />
			}<br />
<br />
<br />
<br />
	//	WinExec("E:\\work\\work\\InspectnPro\\InspectnPro\\debug\\InspectnPro.exe",SW_SHOW);<br />
			STARTUPINFO startinfo;<br />
			RtlZeroMemory(&startinfo,sizeof(STARTUPINFO));<br />
			startinfo.cb=sizeof(STARTUPINFO);<br />
			startinfo.lpReserved = NULL;<br />
			startinfo.lpReserved2 = NULL; <br />
			startinfo.cbReserved2 = 0;<br />
			startinfo.lpDesktop = NULL; <br />
			startinfo.dwFlags = 0;<br />
			PROCESS_INFORMATION pinfo;<br />
			RtlZeroMemory(&pinfo,sizeof(PROCESS_INFORMATION));<br />
			CreateProcess(NULL,<br />
						_T("E:\\work\\work\\InspectnPro\\InspectnPro\\debug\\InspectnPro.exe"),<br />
						NULL,<br />
						NULL,<br />
						TRUE,<br />
						NULL,<br />
						NULL,<br />
						NULL,<br />
						&startinfo,<br />
						&pinfo);

sam_psycho14-Jan-09 19:12

sam_psycho

14-Jan-09 19:12

How I can Move dailog box by clicking anywhere not only on caption bar? Smile | :)

Thanks .

Re: Moving dailog box by clicking anywhere not only on caption bar?

Naveen14-Jan-09 19:24

Naveen

14-Jan-09 19:24

sampat wrote:
How I can Move dailog box by clicking anywhere not only on caption bar?

Handle the LButtonDown message and send the WM_NCLBUTTONDOWN, message from it as follows

void CMYDlg::OnLButtonDown(UINT nFlags, CPoint point) 
{	
	SendMessage( WM_NCLBUTTONDOWN, HTCAPTION, (LPARAM) MAKELPARAM( point.x, point.y) );	
	CDialog::OnLButtonDown(nFlags, point);
}

nave

[OpenedFileFinder] [My Blog]

Re: Moving dailog box by clicking anywhere not only on caption bar?

sam_psycho14-Jan-09 22:32

sam_psycho

14-Jan-09 22:32

Thanx buddy .... everything is solved Smile | :)

Re: Moving dailog box by clicking anywhere not only on caption bar?

«_Superman_»14-Jan-09 22:40

«_Superman_»

14-Jan-09 22:40

The solution given by NS is the right way to do it.

«_Superman_»

Re: Moving dailog box by clicking anywhere not only on caption bar?

Nishad S14-Jan-09 19:33

Nishad S

14-Jan-09 19:33

Like this... Smile | :)

UINT CTestDlg::OnNcHitTest(CPoint point) 
{
	return HTCAPTION;
}

But if you want to be more specific, try the following... it will exclude the borders, menu, etc.

UINT CTestDlg::OnNcHitTest(CPoint point) 
{
	UINT uHitTest = CDialog::OnNcHitTest(point);
	if( uHitTest == HTCLIENT ) return HTCAPTION;
}

- ns -

Re: Moving dailog box by clicking anywhere not only on caption bar?

Jijo.Raj14-Jan-09 21:49

Jijo.Raj

14-Jan-09 21:49

Paul DiLascia's article[^] will be interesting.

Regards,
Jijo.

_____________________________________________________

http://weseetips.com[^] Visual C++ tips and tricks. Updated daily.

Error LNK2005 ( extern variable)

Arif Liminto14-Jan-09 15:17

Arif Liminto

14-Jan-09 15:17

Hi ,I am new in mfc and c++, and currently I have got problem with this kind of error

basically , i have to file get.cpp and send.cpp

and i want to share variable across that files

and i thought we can use keyword "extern"

so here is my code

in send.h

int g_iEnabled

class csend
{
......
}

in get.h

extern int g_iEnabled

class cget
{
....
}

is that the rightway to share variable across multiple files

thanks for your help

bye Big Grin | :-D

Re: Error LNK2005 ( extern variable)

«_Superman_»14-Jan-09 16:51

«_Superman_»

14-Jan-09 16:51

Put the int g_iEnabled declaration in the .cpp file.

«_Superman_»

Re: Error LNK2005 ( extern variable)

Arif Liminto14-Jan-09 17:03

Arif Liminto

14-Jan-09 17:03

Hi thanks men for the solution, it works perfectly

How to debug a program for unknown error??

Kiran Satish14-Jan-09 12:11

Kiran Satish

14-Jan-09 12:11

Hi all,

The question might be strange, but I have a MFC application (say on client system) which will be started by another program from another system (say server) using PsTools command via network. Both systems are connected using a crossover cable and once the server starts the client program it sends commands to client as per user request on server program (which is also a MFC program). The client program is multi-threaded program and records/playbacks videos from framegrabber. Everything is fine for a while, but recently the client program started acting weird, the program closes abruptly without any warning or message or anything, it just disappears (not even its trace in task manager) while the server is still running, the client should close only when the server sends a quit ('Q') command. I tried to have a message pop up in 'OnClose()' function etc etc, but nothing works, it just disappears randomly.
I wonder if there is any way to figure out what the problem/error is, any suggestions??

thanks,
-PNT.

PKNT

Stephen Hewitt14-Jan-09 13:51

Stephen Hewitt

14-Jan-09 13:51

I've seen this happen when an exception is raised and the EXCEPTION_REGISTRATION linked list is corrupt. See here[^] for more information. The following program demonstrates this (it's from memory so bear with me):

void main()
{
	// Corrupt 'EXCEPTION_REGISTRATION' linked list. Here we corrupt the
	// head pointer, but in real life it's more likely a corruption of the
	// chain itself on the stack.
	__asm
	{
		 mov eax, 0
		 mov FS:[0], eax
	}
 
	// Generate an exception.
	*(char*)0 = 0;
 
	return 0;
}

Steve

Randor 14-Jan-09 14:50

Randor

14-Jan-09 14:50

In addition to what Stephen Hewitt pointed out... there are other situations which may cause the symptoms you are describing. For example... if you have a global structured exception handler and a second exception occurs while inside your handler code... the application will simply be terminated and would 'dissapear'.

Another situation which would cause the application to 'just dissapear' would be calling:

SetErrorMode(SEM_FAILCRITICALERRORS | SEM_NOGPFAULTERRORBOX);

This single line of code would cause the application to simply dissapear when an exception occured.

I would suggest downloading Debugging Tools for Windows[^] and attaching WinDbg to a debug build of your application.

Best Wishes,
-David Delaune

Kiran Satish14-Jan-09 15:52

Kiran Satish

14-Jan-09 15:52

Thanks for your replies, I thought of using WinDbg, but couldnt figure out exactly how to use it. But will check out for some articles on it. BTW in my program there are no stacks or heavy memory allocations or anything memory intensive, its just get the frame data from framegrabber and write it to a raw avi file on the hard drive.

Will try WinDbg to find the problem.

-PNT

PKNT