Re: Problem with Hooks - C / C++ / MFC Discussion Boards

JensB4-Mar-04 20:12

4-Mar-04 20:12

Hi
I have created a service out of a program using the program SRVANY.EXE.

When you click the minimise button of the program, an icon of the program is automatically added to the tray bar. When you double click the icon, the program is shown.

Now, when i minimise the program, which runs as interactive service with local system account .. it is added to the tray bar. When i log out and then log in, the icon is removed from the tray bar and i still can see the program (process) in my task manager so it still runs.

I thought my code removed the icon itself, so i checked that but the 'WM_DESTROY' isn't send by the system when you logout so my program doesn't remove it itself (Windows does).

Is there any way around this? And does anyone know which messages the service manager sends to the program to stop or reboot? I would highly appreciate any help.

Best regards,
Jens

Re: Services - Advanced -

Prakash Nadar4-Mar-04 20:17

Prakash Nadar

4-Mar-04 20:17

I guess it is due to recreation of the tasktray and you are not notified and you are not putting ur icon back on the tasktray....
you should listen to the user defined message with message string "TaskbarCreated"

like this
const UINT WM_TASKBARCREATE = RegisterWindowMessage(_T("TaskbarCreated"));

when you get this message update the taskbar icon.

Re: Services - Advanced -

JensB4-Mar-04 20:23

JensB

4-Mar-04 20:23

ah ok. I will try this right now.

Greetings,
Jens

Re: Services - Advanced -

JensB4-Mar-04 20:45

JensB

4-Mar-04 20:45

Yes, now i get the Windows message that the tray bar is created and i add my icon to it. So that problem is solved Smile | :)

Thanks alot!

However, i got one problem left. Every time when i run the service and log off and then i login a second time .. the program is shown correctly with an interface (interactive using local system account). But i can't use the menu .. it's somehow impossible to use the menu or do some actions with the program. How is this possible? (never had that problem until i used it as service)

<just edited="">
I only have this weird problem on my computer. On any other computer it works great.

Greetings,
Jens

Re: Services - Advanced -

Prakash Nadar4-Mar-04 21:26

Prakash Nadar

4-Mar-04 21:26

I am glad that it worked. Smile | :)

Sorry, no idea about the problem, i never had this problem before, so i have little idea about it.

Frown | :(

Problem with Hooks

bilal784-Mar-04 19:17

bilal78

4-Mar-04 19:17

Hi All!
I am using SetWindowsHookEx(...) to set WH_CBT hook, but the problem is that it never get called in system context. But only works on my application's main window. Don't know whats wrong? May be i am missing a simple thing that is causing the hook to install as system wide.

Here is the piece of code i am using to install the hook

//Installs the hook
//g_hInstDll is set to hInstance in DllMain()
g_hHook = SetWindowsHookEx(WH_CBT,(HOOKPROC)Dll_HookProc,(HMODULE)g_hInstDll,0);

Is there anything specific i need to do in order to install hook system wide?

Best Regards,
Bilal Anjum

Re: Problem with Hooks

Mike Beckerleg5-Mar-04 1:11

Mike Beckerleg

5-Mar-04 1:11

The call to SetWindowsHookEx looks fine, what does it return when you call it?

I assume Dll_HookProc is in a DLL and is of the correct type.

Re: Problem with Hooks

bilal787-Mar-04 17:58

bilal78

7-Mar-04 17:58

g_hHook is a proper handle and yes all of this is within the DLL. Here is the piece of code:

//defined as DLL_USE __declspec(dllexport) OR __declspec(dllimport)<br />
BOOL DLL_USE WINAPI Dll_HookApp()<br />
{<br />
	g_hHook = SetWindowsHookEx(WH_CBT,(HOOKPROC)Dll_HookProc,(HMODULE)g_hInstDll,(DWORD)NULL);<br />
	if (g_hHook)<br />
		return TRUE;<br />
	else<br />
		return FALSE;<br />
}<br />
<br />
BOOL DLL_USE WINAPI Dll_UnhookApp()<br />
{<br />
	if (g_hHook != NULL)<br />
        	return ::UnhookWindowsHookEx(g_hHook);<br />
	else<br />
		return FALSE;<br />
}<br />
<br />
static LRESULT CALLBACK Dll_HookProc(int nCode, WPARAM wParam, LPARAM lParam)<br />
{<br />
	LRESULT lRes = 0;<br />
<br />
	if(nCode < 0)<br />
		return CallNextHookEx(g_hHook, nCode, wParam, lParam);<br />
<br />
	//Some operations<br />
<br />
	return lRes;<br />
}

Best Regards,
Bilal Anjum

Re: Problem with Hooks

Mike Beckerleg7-Mar-04 22:51

Mike Beckerleg

7-Mar-04 22:51

The only difference I can see between your code and the code I have written is in the definition of the callback function. Mine is defined as:

DLL_USE LRESULT CALLBACK CBTHandler(int nCode, WPARAM wParam, LPARAM lParam)<br />
{<br />
// do stuff here<br />
}

So it is not static and it is marked as exported from the DLL. This could be causing the problems.

Mike

Re: Problem with Hooks

bilal788-Mar-04 1:07

bilal78

8-Mar-04 1:07

well static can be or is unnecessary but exporting the Hook proc doesn't make any sense, coz the calling application can only set the hook or remove the hook, hook proc will be used internally, so i think need not to export the hook proc.
Anyway thanks a lot for the reply, if you have some suggestion like setting up my project (i am using VC++ 6 may be i am not setting up the project), then it might be helpful.

if you can send me the basic code for your hook dll (Only hook setup code), it can solve the issue.
Best Regrads,
Bilal Anjum

Re: Problem with Hooks

Mike Beckerleg9-Mar-04 3:13

Mike Beckerleg

9-Mar-04 3:13

My basic code is the same as yours apart from the definition of the hook function.

The DLL will be loaded into the adderess space of all the other application running on your system, they will call the hook function so exporting it could make a difference. Try it, it will only take a minute to test it.

Re: Problem with Hooks

bilal789-Mar-04 17:37

bilal78

9-Mar-04 17:37

Hi!
I have solved my problem, infact there was no problem at all. What i was trying to do was to debug a system wide installed hook in the VC debugger, which is not possible as such, so all the events i got were from the application i was dubugging in context with. So if i run the program (not debug it), it works fine. Thanks a lot for your patience and help. Now the real problem is still there, how to debug my program (system wide hook)?

Best Regards,
Bilal Anjum

How to get Users and their rights of current system?

.NetRams4-Mar-04 17:53

.NetRams

4-Mar-04 17:53

Hi Everybody,
Is there any API Confused | :confused:

to get the users of my machine.
Also to check their rights.

Thanks in Advance
iRams

Get MAC address (exclude VPN adp)

gilc1374-Mar-04 15:59

gilc137

4-Mar-04 15:59

I'm currently trying to get valid MAC address from ethernet adapters in C++ using the following methods:-

netbios, snmp & getadapterinfo.

I have the programs only retrieving adapter type 6 which are ethernet adapters.

I have an instance where a P.C has VPN software & the VPN adapter gets pick up as a adapter type 6. The VPN adapter description is "NOC EXTRANET ACCESS ADAPTER".

Is there anyway to exclude virtual adapters?, I need to do this for liecensing purposes within our software applications.

Any help would be appreciated.

Thanks in advance

Gilc137

how to receive app launch message?

chpsoft4-Mar-04 14:28

chpsoft

4-Mar-04 14:28

I switch the default desktop to mine,and i produce taskbar myself.So i want to receive some message when system shell is ready to launch an application and to terminate an application.
how can i do? hook? or other?

Re: how to receive app launch message?

Joel Lucsy4-Mar-04 16:00

Joel Lucsy

4-Mar-04 16:00

Typically you'd use SetWindowsHookEx with either the WH_CBT or WH_SHELL setting.

--
Joel Lucsy

Re: how to receive app launch message?

chpsoft4-Mar-04 16:16

chpsoft

4-Mar-04 16:16

thank you.
But can you give me a demo code?or where can download such demo?
thank you again.

Re: how to receive app launch message?

bilal784-Mar-04 19:30

bilal78

4-Mar-04 19:30

Hi!
You will use WH_CBT hooks and look for HCBT_CREATEWND nCode on your hook proc. You will find an example for this at
http://www.codeproject.com/shell/sweeptheminesweeper.asp?target=minesweeper[^]

Regards,
Bilal Anjum

Re: how to receive app launch message?

chpsoft4-Mar-04 19:58

chpsoft

4-Mar-04 19:58

can you tell me what's the difference of HCBT_CREATEWND and HSHELL_WINDOWCREATED?

Re: how to receive app launch message?

bilal784-Mar-04 20:26

bilal78

4-Mar-04 20:26

HI!
Well according to MSDN (If its wrong it's Microsoft to blame Smile | :)

)

HSHELL_WINDOWCREATED will be called when "A top-level, unowned window has been created. The window exists when the system calls a ShellProc function."
and
HCBT_CREATEWND will be called when "A window is about to be created. The system calls the hook procedure before sending the WM_CREATE or WM_NCCREATE message to the window. If the hook procedure returns a nonzero value, the system destroys the window; the CreateWindow function returns NULL, but the WM_DESTROY message is not sent to the window. If the hook procedure returns zero, the window is created normally."

Regards,
Bilal Anjum

Re: how to receive app launch message?

chpsoft4-Mar-04 20:41

chpsoft

4-Mar-04 20:41

i see!thank you!

Shared Folders With Username/Password

shultas4-Mar-04 13:50

shultas

4-Mar-04 13:50

Hey all.

I've got a tiny helper application that I've built that creates text files on a network/shared drive.

I'm presently just using CStdioFile to create the text files.

The problem that I am running into is username/password authentication. I don't really know where to start for this and would appreciate some pointers in the right direction. The network/shared drive is "\\S-CPU1\c\the_folder". If I open up IE, and go to \\S-CPU1\c\the_folder ... the first time I try it, IE asks for the username/password. I enter it in, it goes there. I can then close out of IE and it "remembers" the username/password combination (or keeps me logged in to it, or whatever) until I physically LOG OUT or switch users. So, if I do that one time, I can then run my helper app, and it creates the files over on that shared folder without a problem.

The problem is I would like to automate this, so that I/the user does not have to first bring up IE and go through that process (and I don't want to physically MAP a drive to that folder). I would like to be able to run my app, and if it realizes that it needs a user/password to access that folder, it will go ahead and bring up a prompt asking the user for that information. After that point, it'll just roll through and do it's thing.

I've searched for several phrases in the articles on this site, but can not seem to find anything that is doing what I want. If someone could point me in the right direction, I would greatly appreciate it.

Shultas

Re: Shared Folders With Username/Password

sunyou4-Mar-04 19:17

sunyou

4-Mar-04 19:17

DWORD WNetAddConnection2(
LPNETRESOURCE lpNetResource, // connection details
LPCTSTR lpPassword, // password
LPCTSTR lpUsername, // user name
DWORD dwFlags // connection options
);

lpLocalName :Points to a null-terminated string that specifies the name of a local device to redirect, such as "F:" or "LPT1". The string is treated in a case-insensitive manner.
If the string is empty, or if lpLocalName is NULL, the function makes a connection to the network resource without redirecting a local device.

nmake and the c++ build tool.

debutante4-Mar-04 13:36

debutante

4-Mar-04 13:36

how do i change a program which wae built to compile with nmake to compile
with the c++ build tool.

please help

Re: nmake and the c++ build tool.

David Crow4-Mar-04 13:39

David Crow

4-Mar-04 13:39

You should be able to open the .mak file with Visual Studio.

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