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Richard MacCutchan wrote: although in the second case you could easily overwrite the buffer if you are not careful.
Did you mean overrun, didn't you?
BTW: Good answer, my 5.
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
[My articles]
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Well spotted!
Odd how it looked quite sensible when I wrote it.
Unrequited desire is character building. OriginalGriff
I'm sitting here giving you a standing ovation - Len Goodman
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First off, I'm real new to C++ so hopefully I state things right and I'm in the correct forum.
I'm tinkering with some code to use the CreateProcessWithTokenW function (http://msdn.microsoft.com/en-us/library/windows/desktop/ms682434(v=vs.85).aspx). Now, everything works just fine when I run it on Windows 7. But if I run it on XP, it bombs out with an error message about the procedure entry point not being located in the dynamic link library ADVAPI32.dll.
So what do I need to do to either make this work on XP, or else drop back to using CreateProcessAsUser on Windows XP, but still use CreateProcessWithTokenW on Windows 7?
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According to this page[^], it is not supported on XP. The minimum supported client is Windows Vista. 
Chris Meech
I am Canadian. [heard in a local bar]
In theory there is no difference between theory and practice. In practice there is. [Yogi Berra]
posting about Crystal Reports here is like discussing gay marriage on a catholic church’s website.[Nishant Sivakumar]
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Hi,
I am very happy to hear that you went straight to MSDN to get your answers. That is definitely a working recipe for becoming a better software engineer. When you are reading these MSDN function descriptions... always scroll to the bottom... the MSDN almost always gives which library the function is being exported from (in this case Advapi32.dll) and the minimum operating system/service pack required. You have obviously already discovered that the minimum OS is Vista for this function.
If you already have an access token then you should use the CreateProcessAsUser function[^]
Lucidation wrote: So what do I need to do to either make this work on XP, or else drop back to using CreateProcessAsUser on Windows XP, but still use CreateProcessWithTokenW on Windows 7?
I would personally recommend using CreateProcessAsUser for both scenarios. Why create two code paths? CreateProcessAsUser should work for XP all the way to Win7Sp1.
Best Wishes,
-David Delaune
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As suggested in Database forum, I am reposting this here.
I am having an issue with retrieving fields from MFC CRecordset.
I am using GetFieldValue( index, strText );
Works fine until the opened recordset contains initially only one record. Than I get the first field OK, but then I get an error saying basically that the field has already been retrieved.
Here it the error:
Error: GetFieldValue operation failed on field %d.
Data already fetched for this field.
It seem that the field index is not being advanced.I stepped thru the GetFieldValue,
but cannot find the actuall source for the error routine.
If I do MoveFirst on this one record record set , I get an error that I am attempting to move past the beginning of the recordset.That would be expected.
I am using VC 6.0 MFC with standard CRecordset and Access database with ODBC.
So far Google is no help.
Any pointers would be greatly appreciated.
Thanks for your help.
Vaclav
Addendum
I am trying to use DoDataExchange to see if it behaves differently. I need recode to do that.
SOLVED ???
Solved by checking for number of records and when it is 1 I add a new record.
recordset->AddNew();
Funny part - checking the count again it counts 1 , not two!
Kluge , but it works. Sure would like to know why it fails initially.
Vaclav
-- modified 16-Dec-11 16:14pm.
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Vaclav_Sal wrote: It seem that the field index is not being advanced.
There is nothing in the code you have shown where an attempt is made to advance the index value.
Unrequited desire is character building. OriginalGriff
I'm sitting here giving you a standing ovation - Len Goodman
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True, but I did state that the code works untill only one record is INITIALLY in the recordset.
So here it is, mind that it is a code under construction.
short nFields = pRecordset->GetODBCFieldCount( );
//pRecordset->MoveFirst( );
while( !pRecordset->IsEOF( ) )
{
//pRecordset->DoFieldExchange(PDX);
buffer = strText.GetBuffer(256);
// insert dummy item to list
if(!pList->InsertItem(iItem,buffer,NULL))
{
// TRACE("\n buffer %s ",buffer);
};
// set item text
for( short index = 0; index < nFields; index++ )
{
This is where it fails
pRecordset->GetFieldValue( index, strText );
This is where it fails and the index is 1 during the failure
if(!strText.CompareNoCase("48")) this is retruned with index = 0
TRACE("\n");
TRACE("\nstrText %s ", strText);
buffer = strText.GetBuffer(256);
pList->SetItemText(iItem,index,buffer);
TRACE("\n item %i field %i buffer %s ",iItem , index , buffer );
strText ="";
}
pRecordset->MoveNext( );
iItem++;
}
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Just so I understand what is going on I am going to put comments in the code. Tell me if I am wrong. And this will work until you get to the last row or does it fail at the first row?
while( !pRecordset->IsEOF( ) )
{
buffer = strText.GetBuffer(256);
if(!pList->InsertItem(iItem,buffer,NULL))
{
};
for( short index = 0; index < nFields; index++ )
{
This is where it fails
pRecordset->GetFieldValue( index, strText );
This is where it fails and the index is 1 during the failure
if(!strText.CompareNoCase("48")) this is retruned with index = 0
TRACE("\n");
TRACE("\nstrText %s ", strText);
buffer = strText.GetBuffer(256);
pList->SetItemText(iItem,index,buffer);
TRACE("\n item %i field %i buffer %s ",iItem , index , buffer );
strText ="";
}
pRecordset->MoveNext( );
iItem++;
}
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It fails when the recordset has only one record / row after it is first open.
It works fine when the recordset has more than one record / rows and it will retrieve them all. I cannot run it now because it is a part of other code. But if you look at the MFC thread you will note where exactly it reports the trouble.
Basically it does not see the data, but the error message is misleading due to silly MS coding error ( wrong / missing paramaters in TRACE).
Sorry, some of the stuff I am reffering to is in this thread.
Your comments are OK. Keep in mind it only fails as I mentioned above.
The loops are OK.
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FYI found the reason - there is no data found!
This is the routine reporting it. Observe the lack of correct code for
nFieldIndex - 1!
Now I need to find out why - the data is there!
long PASCAL CRecordset::GetData(CDatabase* pdb, HSTMT hstmt,
short nFieldIndex, short nFieldType, LPVOID pvData, int nLen,
short nSQLType)
{
UNUSED(nSQLType);
long nActualSize;
RETCODE nRetCode;
// Retrieve the column in question
AFX_ODBC_CALL(::SQLGetData(hstmt, nFieldIndex,
nFieldType, pvData, nLen, &nActualSize));
// Ignore data truncated warnings for long data
if (nRetCode == SQL_SUCCESS_WITH_INFO)
{
#ifdef _DEBUG
CDBException e(nRetCode);
if (afxTraceFlags & traceDatabase)
{
CDBException e(nRetCode);
// Build the error string but don't send nuisance output to TRACE window
e.BuildErrorString(pdb, hstmt, FALSE);
// If not a data truncated warning on long var column,
// then send debug output
if ((nSQLType != SQL_LONGVARCHAR &&
nSQLType != SQL_LONGVARBINARY) ||
(e.m_strStateNativeOrigin.Find(_afxDataTruncated) < 0))
{
TRACE1("Warning: ODBC Success With Info on field %d.\n",
nFieldIndex - 1);
e.TraceErrorMessage(e.m_strError);
e.TraceErrorMessage(e.m_strStateNativeOrigin);
}
}
#endif // _DEBUG
}
else if (nRetCode == SQL_NO_DATA_FOUND)
{
NICE Mr Bill
TRACE0("Error: GetFieldValue operation failed on field %d.\n");
TRACE1("\tData already fetched for this field.\n",
nFieldIndex - 1);
NICE Mr Bill
AfxThrowDBException(nRetCode, pdb, hstmt);
}
else if (nRetCode != SQL_SUCCESS)
{
TRACE1("Error: GetFieldValue operation failed on field %d.\n",
nFieldIndex - 1);
AfxThrowDBException(nRetCode, pdb, hstmt);
}
return nActualSize;
}
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I have changed the CString in pRecordset->GetFieldValue( index, varValue );
to CDBVariant varValue.
Same problem - only first field is retrieved.
Identical record is retrieved when different SQl is used and more than one record are retrieved. So the data is there.
The first field is AutoNumber in Access and the rest of fields are Text.
I may have to insert dummy record to make this play.
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Vaclav_Sal wrote: It seem that the field index is not being advanced.I stepped thru the GetFieldValue,
but cannot find the actuall source for the error routine.
Have you looked at CRecordset::GetData() in dbcore.cpp?
Vaclav_Sal wrote: If I do MoveFirst on this one record record set , I get an error that I am attempting to move past the beginning of the recordset.That would be expected.
So do you need to call IsBOF() first?
"One man's wage rise is another man's price increase." - Harold Wilson
"Fireproof doesn't mean the fire will never come. It means when the fire comes that you will be able to withstand it." - Michael Simmons
"Show me a community that obeys the Ten Commandments and I'll show you a less crowded prison system." - Anonymous
modified 19-Dec-11 8:19am.
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No, I just did it to test stuff.
Actually, the "solution" is to do AddNew to any recordset without doing any checking if there is only one record in recordset.Real hack.
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Vaclav_Sal wrote: No, I just did it to test stuff.
Did what?
"One man's wage rise is another man's price increase." - Harold Wilson
"Fireproof doesn't mean the fire will never come. It means when the fire comes that you will be able to withstand it." - Michael Simmons
"Show me a community that obeys the Ten Commandments and I'll show you a less crowded prison system." - Anonymous
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So do you need to call IsBOF() first?
Sorry, I just read only this part. So I answered that.
My appology.
I'll check the GetData.
Vaclav
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I have an application which has several extern variables, I need to access them inside dll. Is that possible?
modified 16-Dec-11 2:58am.
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You may, for instance, pass them (their pointers or references) as parameters of a DLL function.
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
[My articles]
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Thanks,
I agree the way you are saying is right and genuine. But unfortunately I don't have exe's source code
I have injected a dll into exe's process space and now want to get the data from exe's memory space. I tried with hooking the system level functions like LoadLibrary and TextOut etc but I could not hook GetProfileInt, CString's sprintf, format etc functions.
Any way to do so ?
I wonder who downvoted my question 
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So you're an hacker?!
I upvoted your question for balancing.
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
[My articles]
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Nopes! I am not; but I like to explore the things at extreme level 
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Use a shared header externing the variable in the dll. Include this in the exe, and then the linker will do the rest for you.
==============================
Nothing to say.
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Thanks Eric,
But I don't have exe's code. See my above reply for more details.
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you can access extern (and exported) variables in a DLL from an EXE.
you cannot access variables in an EXE from a DLL.
you could, in theory, decompile the EXE, find the references to the data you want, figure out if the data is statically or dynamically allocated, then create some mechanism to probe the EXE's memory at the right locations and times, etc.. a huge task.
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Thanks Chris for verifying that I cannot access variables in an EXE from a DLL directly.
So I am doing the Huge task. Still I think hooking should work as it is working for few of the functions; I will try a little more before leaving hooks.
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