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See - How to tell if the current user is in administrators group programmatically
http://blogs.msdn.com/junfeng/archive/2007/01/26/how-to-tell-if-the-current-user-is-in-administrators-group-programmatically.aspx[^]
You can use CheckTokenMembership (http://msdn2.microsoft.com/en-us/library/aa376389.aspx) to check whether a user is in administrators group. There is an example in the MSDN document.
The example will not work in Windows Vista. In Windows Vista, even if the user is in administrators group, the OS will create a filtered user token when user log on. The SID of administrators group is not included in the filtered user token. The full token is linked to the filtered user token, and can be retrieved with API GetTokenInformation with the new TokenLinkedToken information type.
The following is the sample code. You need to download Vista SDK to compile it. Please make sure you read the article in the reference section.
HRESULT IsUserAdmin(BOOL *pIsAdmin)
{
int b;
HANDLE hProcess = NULL;
HANDLE hProcessToken = NULL;
HANDLE hLinkedToken = NULL;
BOOL fIsAdmin = FALSE;
DWORD dwLength = 0;
OSVERSIONINFO osver = {sizeof(OSVERSIONINFO)};
HRESULT hr = S_OK;
*pIsAdmin = FALSE;
// get handle to our process token
hProcess = GetCurrentProcess();
if (!OpenProcessToken(hProcess, TOKEN_QUERY, &hProcessToken))
{
hr = HRESULT_FROM_WIN32(GetLastError());
goto Exit;
}
// get admin SID
char AdminSID[SECURITY_MAX_SID_SIZE];
dwLength = sizeof(AdminSID);
if(!CreateWellKnownSid(WinBuiltinAdministratorsSid, NULL, &AdminSID, &dwLength))
{
hr = HRESULT_FROM_WIN32(GetLastError());
goto Exit;
}
// check to see if the current token contains admin SID
if (!CheckTokenMembership( NULL, &AdminSID, &fIsAdmin))
{
hr = HRESULT_FROM_WIN32(GetLastError());
goto Exit;
}
if (fIsAdmin)
{
// printf("The user is in admin group, and the process is elevated.\n");
*pIsAdmin = TRUE;
goto Exit;
}
// if the current token does not contain admin SID, it does not mean
// that the current user is not admin. In Vista by default the token of
// users in administrator group has the the admin SID filtered. We nee
// to use the unfiltered token to do the check.
if (!GetVersionEx(&osver))
{
hr = HRESULT_FROM_WIN32(GetLastError());
goto Exit;
}
// XP and below, we are done.
if (osver.dwMajorVersion < 6)
{
// printf("The user is not in admin group.\n");
goto Exit;
}
// get handle to linked token (will have one if we are lua)
if (!GetTokenInformation( hProcessToken,
TokenLinkedToken,
(VOID*) &hLinkedToken,
sizeof(HANDLE),
&dwLength) )
{
b = GetLastError();
if ( b == ERROR_NO_SUCH_LOGON_SESSION
|| b == ERROR_PRIVILEGE_NOT_HELD)
{
// printf("The user is not in admin group.\n");
goto Exit;
}
hr = HRESULT_FROM_WIN32(b); // a real error
goto Exit;
}
if (!CheckTokenMembership( hLinkedToken, &AdminSID, &fIsAdmin))
{
hr = HRESULT_FROM_WIN32(GetLastError());
goto Exit;
}
if (fIsAdmin)
{
// printf("The user is in admin group, and the process is not elevated.\n");
*pIsAdmin = TRUE;
}
else
{
// printf("The user is not in admin group.\n");
}
Exit:
if (hProcess)
{
CloseHandle(hProcess);
}
if (hProcessToken)
{
CloseHandle(hProcessToken);
}
if (hLinkedToken)
{
CloseHandle(hLinkedToken);
}
return hr;
}
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Hello everyone,
Two basic questions about function invocation from STA to MTA.
1.
In my understaning, the owning thread of STA should not touch MTA component, and also in MTA there is no message queue for MTA owning thread to pumping messages.
My question is, if the owning thread of STA calls MTA component (by interface pointer), which thead is responsible for executing in MTA? From my above analysis, seems both STA owner thread (can not touch MTA component) and MTA owner thread (can not receive calls from STA through message queue, snice no message queue in MTA.)
2.
Before function call returns from MTA, will STA thread waiting or it could execute in asynchronous way?
thanks in advance,
George
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I need to get the color from a specific pixel on the screen.
this pixel is not a part of my console application.
my basic method is:
keybd_event(VK_SNAPSHOT,0x9e, 0, 0);
keybd_event(VK_SNAPSHOT,0x9e, KEYEVENTF_KEYUP, 0);
if(OpenClipboard(NULL))
{
HBITMAP hClipboardBmp = (HBITMAP) GetClipboardData(CF_BITMAP);
}
but i wonder if theres a way to get that pixel(s) directly from the screen.
thank you very much for your time and effort 
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HDC hdc = GetDC(NULL);
COLORREF cr = GetPixel(hdc, x,y);
ReleaseDC(hdc);
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke
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it's perfect, thank you very much! 
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It seems you need toget pixel of a bmp file that you read of clipboard,right?
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Hello everyone,
I posted the code and related compile error below. My analysis below,
1. I think the reason of compile error is, the copy constructor of Goo accepts const reference as input parameter, so the pf member of input parameter is also treated const?
2. And since auto_ptr does not have a copy constructor which accepts const reference auto_ptr as input parameter, the compile error occurs.
My analysis (1) and (2) are both correct?
What makes me confused is it seems the compile error message does not reflect my analysis (1) and (2) above. Any ideas?
#include <memory>
using namespace std;
class Foo {
};
class Goo {
public:
auto_ptr<Foo> pf;
Goo (const Goo& input)
{
this -> pf = input.pf;
}
};
1>d:\visual studio 2008\projects\test0330\test0330\main.cpp(18) : error C2679: binary '=' : no operator found which takes a right-hand operand of type 'const std::auto_ptr<_Ty>' (or there is no acceptable conversion)
1> with
1> [
1> _Ty=Foo
1> ]
1> d:\program files\microsoft visual studio 9.0\vc\include\memory(689): could be 'std::auto_ptr<_Ty> &std::auto_ptr<_Ty>::operator =<Foo>(std::auto_ptr<_Ty> &) throw()'
1> with
1> [
1> _Ty=Foo
1> ]
1> d:\program files\microsoft visual studio 9.0\vc\include\memory(701): or 'std::auto_ptr<_Ty> &std::auto_ptr<_Ty>::operator =(std::auto_ptr<_Ty> &) throw()'
1> with
1> [
1> _Ty=Foo
1> ]
1> d:\program files\microsoft visual studio 9.0\vc\include\memory(707): or 'std::auto_ptr<_Ty> &std::auto_ptr<_Ty>::operator =(std::auto_ptr_ref<_Ty>) throw()'
1> with
1> [
1> _Ty=Foo
1> ]
1> while trying to match the argument list '(std::auto_ptr<_Ty>, const std::auto_ptr<_Ty>)'
1> with
1> [
1> _Ty=Foo
1> ]
thanks in advance,
George
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IMHO your analysis is correct (both point 1 and 2. However, with regard to point 1, my interpretation is: since Goo copy constructor declares its argument const, then its content cannot be modified, but assigment operator of auto_ptr modify its argument, hence the problem).
George_George wrote: What makes me confused is it seems the compile error message does not reflect my analysis (1) and (2) above. Any ideas?
I think that (it's just an hypothesis), since no auto_ptr copy constructor can match the this -> pf = input.pf;, the compiler tries to search for an assignment operator match, but it fails again and gives such error.
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke
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Cool, CPallini!
1.
CPallini wrote: I think that (it's just an hypothesis), since no auto_ptr copy constructor can match the this -> pf = input.pf;, the compiler tries to search for an assignment operator match, but it fails again and gives such error.
You mean compiler search for all forms of assignment operator of auto_ptr, then no one matches so the compile errors come?
2.
The source of error is because the basic C++ ruls is violated -- can not assign const reference (input.pf) to non-const reference (input parameter of assignment operator of class auto_ptr)?
regards,
George
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George_George wrote: 1.
CPallini wrote:
I think that (it's just an hypothesis), since no auto_ptr copy constructor can match the this -> pf = input.pf;, the compiler tries to search for an assignment operator match, but it fails again and gives such error.
You mean compiler search for all forms of assignment operator of auto_ptr, then no one matches so the compile errors come?
Yes, I think so.
George_George wrote: 2.
The source of error is because the basic C++ ruls is violated -- can not assign const reference (input.pf) to non-const reference (input parameter of assignment operator of class auto_ptr)?
Yes.
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke
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Thanks CPallini,
Question answered! Cool!!
regards,
George
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say i have a function int fun(int *a),
and other function int fa(); int fb(), int fc(),....int fn();
all the them will call the fun(int *a),
but the problem is, when I run the program, the vc++ tells me some of them pass the NULL pointer to the fun(int *a) which make mistake, but could not tell me which function calls the fun(int *a) and then pass the NULL pointer to it,
so dear guys, how could I know which one call the fun(int *a) that pass the NULL pointer?
Thanks.
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 I didn't really understand your problem. Do you have a crash and would like to find the problem ? If yes, did you use your debugger to track the problem ? Using the callstack you'll be able to find which function passed a NULL pointer.
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Hi,
If your program stops with runtime error, as Cedric said, use the "call stack" window and see which one of fa(), fb().. fn() is called just before fun().
Or try using only one function from fa(), fb() ... fn() at a time
and find out.
If you have problem still post the relevant code snippet.
Best Regards,
Suman
--
"Programming is an art that fights back!"
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Well one way like others said, if you are programming in Visual Studio, you can set break point and check the call stack when program crashes.
Another way is to do it like this:
int fa()<br />
{<br />
int* a;<br />
.<br />
.<br />
.<br />
if(a == NULL)<br />
{<br />
cout << "fa is the culprit";<br />
}<br />
fun(a);<br />
}
-Saurabh
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Use the debugger to set a breakpoint in fun(). When a equals NULL, check the call stack.
"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
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Did you get runtime error?
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Without asking how to do it, I'd like to ask if it's theoretically possible for me to create my own version of the C++ runtime, and have VC++ link my programs to that instead of the usual one.
Is such a thing possible?
“Cannot find REALITY.SYS...Universe Halted.”
~ God on phone with Microsoft Customer Support
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Yes it's possible.
See the /ENTRY linker option...
Mark
Mark Salsbery
Microsoft MVP - Visual C++
![Java | [Coffee]](https://codeproject.global.ssl.fastly.net/script/Forums/Images/coffee.gif)
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Do you want to make an exe file yourself without vc++ compiler?
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Hi,
I recently moved application resources (dialogs and strings) into a resource only DLL and came across a problem that I don't fully understand... thanks for some help.
As soon as I created my main dialog from the loaded DLL it failed and the debug output showed something like: >>> If this dialog has OLE controls: AfxEnableControlContainer has not been called yet. I traced it back to an owner draw control in the dialog, when I removed this control all worked fine. So I played around a bit with my owner draw control. It is derived from CWnd and tries to register a window class, here is the code:
WNDCLASS wndcls;
HINSTANCE hInst = AfxGetInstanceHandle();
if(!(::GetClassInfo(hInst, MY_CONST_CLASSNAME, &wndcls)))
{
wndcls.style = CS_DBLCLKS | CS_HREDRAW | CS_VREDRAW;
wndcls.lpfnWndProc = ::DefWindowProc;
wndcls.cbClsExtra = wndcls.cbWndExtra = 0;
wndcls.hInstance = hInst;
wndcls.hIcon = NULL;
wndcls.hCursor = AfxGetApp()->LoadStandardCursor(IDC_ARROW);
wndcls.hbrBackground = NULL;
wndcls.lpszMenuName = NULL;
wndcls.lpszClassName = MY_CONST_CLASSNAME;
AfxRegisterClass(&wndcls)
}
After I replaced AfxGetInstanceHandle() with AfxGetResourceHandle() it works. This was just try and error, am I doing it right? Because MSDN says hInstance = "Handle to the instance that contains the window procedure for the class".
/Moak
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Moak wrote: After I replaced AfxGetInstanceHandle() with AfxGetResourceHandle() it works.
It's interesting that it works, since DefWindowProc() isn't in either of your modules
Mark
Mark Salsbery
Microsoft MVP - Visual C++
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Mark now I am more confused 
...did I do something stupid?
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Moak wrote: ...did I do something stupid?
Heh not that I can see off hand. I'm just curious why it works with one HINSTANCE and not
the other...unless one is NULL?
Do you use AfxSetResourceHandle() somewhere?
Mark
Mark Salsbery
Microsoft MVP - Visual C++
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