Issue with strcpy [modified] - C / C++ / MFC Discussion Boards

BabyGuru18-Jun-06 23:04

18-Jun-06 23:04

Experts!
I have a device conected to my computer with a USB,
i want to stop this device and then start it again.
i selected disable in the device manager and the device was disable successfully.

But when i tried to do it programmaticatly it failed.
I tried calling "net stop service_name_blabla" from the command line.
and i tried using SERVICE_CONTROL_STOP,in ControlService

but they both failed, reason:
"The requested control is not valid for this service. " error
how can i disable the service with C++ like i'm doing well in the device manager ?

thanks.
Laugh | :laugh:

Re: Stop Service

Maxwell Chen18-Jun-06 23:56

Maxwell Chen

18-Jun-06 23:56

BabyGuru wrote:
a device conected to my computer with a USB

BabyGuru wrote:
how can i disable the service with C++ like i'm doing well in the device manager ?

Use SetupDiSetClassInstallParams function to do this.

Maxwell Chen

Regarding iTunes SDK for c++

Halid Niyaz18-Jun-06 22:53

Halid Niyaz

18-Jun-06 22:53

Is it possible to use iTunes SDK without installing itunes? Can I use APIs provided by iTunes SDK just by registering the required DLLs and with required files? Please send me some links where I can find sample applications to update iPod(sync) thru our own application which uses iTunes SDK.

Vignesh T R

Re: Regarding iTunes SDK for c++ [modified]

Laxman Auti18-Jun-06 23:00

Laxman Auti

18-Jun-06 23:00

Halid Niyaz wrote:
Is it possible to use iTunes SDK without installing itunes? Can I use APIs provided by iTunes SDK just by registering the required DLLs and with required files? Please send me some links where I can find sample applications to update iPod(sync) thru our own application which uses iTunes SDK.

See the Following link where you get example.

Here[^]

If the Dll uses the Libraries then you have to link that library else it throws linker error.

Knock out 't' from can't,
You can if you think you can
Cool | :cool:

-- modified at 5:01 Monday 19th June, 2006

connect command in mfc [modified]

amit.code18-Jun-06 22:46

amit.code

18-Jun-06 22:46

how to use connect command in mfc . what are the paramaeters which is to be passed to connect to host.

prashant jain

-- modified at 4:53 Monday 19th June, 2006

Re: connect in mfc

_AnsHUMAN_ 18-Jun-06 22:49

_AnsHUMAN_

18-Jun-06 22:49

From the docs :
int connect (
SOCKET s,
const struct sockaddr FAR* name,
int namelen
);
s
[in] A descriptor identifying an unconnected socket.
name
[in] The name of the socket to connect to.
namelen
[in] The length of the name parameter.

Somethings seem HARD to do, until we know how to do them.
Wink | ;-)

_AnShUmAn_

Re: connect in mfc

capricious_00118-Jun-06 22:51

capricious_001

18-Jun-06 22:51

Here have a look at this!

http://msdn2.microsoft.com/en-us/dxt965kz.aspx

Robbie

Issue with strcpy [modified]

capricious_00118-Jun-06 22:43

capricious_001

18-Jun-06 22:43

Hi guys,

I have a function where I am passing a value by reference. Below is the prototype:

bool retrieveLogFileLocation(LPSTR&);

Now within the body of the function definition I have the following function as well.

bool retrieveLogFileLocation(LPSTR& value){
    char[255] lszValue;
    HKEY hKey;
    LONG returnStatus;
    DWORD dwType = REG_SZ;
    DWORD dwSize =255;
    bool success = true;

    RegQueryValueEx(hKey, "InstallationPath", NULL, &dwType, (LPBYTE)&lszValue, &dwSize);

    strcpy(value, lszValue);
}

The problem I am receiving is that whenever my program runs, it crashes instantly, and I know for sure it is an issue with strcpy(value, lszValue). I have tried in multiple ways through type-casting and such to resolve the issue, but I'm perplexed as to whats causing the problem.

Any help would be appreciated Big Grin | :-D

Robbie

-- modified at 4:53 Monday 19th June, 2006

PS: I only included bits and pieces of the function definition simply because the actual function definition is very long. :P

Re: Issue with strcpy

Laxman Auti18-Jun-06 22:53

Laxman Auti

18-Jun-06 22:53

capricious_001 wrote:
Any help would be appreciated

May be the length of the receiving string variable is short as compared to the data you tring to copy into it.

Knock out 't' from can't,
You can if you think you can
Cool | :cool:

Re: Issue with strcpy

capricious_00118-Jun-06 23:04

capricious_001

18-Jun-06 23:04

hmm I didnt initialize the length of the referenced value variable to a certain length.

Actually I dont quite understand what you mean lol.

Robbie

Re: Issue with strcpy

Kevin McFarlane18-Jun-06 23:16

Kevin McFarlane

18-Jun-06 23:16

An alternative way of doing this is to use a string class, e.g., CString. Here's some old code I dug out - look at the last if block - RegQueryValueEx call...

// Retrieves Operator Console ID from "SOFTWARE\Cegelec AEG\CMS\Operator Console" subkey in registry
// Looks for a value name called, e.g., "ID". May return something like "IB101"

long OcipsAutoInterface::GetConsoleIDEx(LPCTSTR pszValueName, CString& strValueData)
{
	HKEY            hkOperatorConsole;
	long			nResult; // return value - ERROR_SUCCESS or some value indicating failure
	unsigned long	nSize;

	// Open subkey to Operator Console
	
	CString strSubKey;
	strSubKey.LoadString( IDS_OP_CONSOLE_SUBKEY ); //e.g., "SOFTWARE\Cegelec AEG\CMS\Operator Console "

	nResult = ::RegOpenKeyEx( HKEY_LOCAL_MACHINE, 
							  LPCTSTR( strSubKey ),
							  0, 
							  KEY_EXECUTE, // Permission for read access
							  &hkOperatorConsole );

	if ( ERROR_SUCCESS == nResult )
	{
		// Search for value name and get size of value data
		nResult = ::RegQueryValueEx( hkOperatorConsole, pszValueName, NULL, NULL, NULL, &nSize );
		
		if ( ERROR_SUCCESS == nResult )
		{
			// Retrieve value data
			
			// ...first return a writeable buffer for the data
			LPTSTR pszValueData = strValueData.GetBuffer( nSize );

			//...then get the data
			nResult = ::RegQueryValueEx ( hkOperatorConsole, pszValueName, NULL, NULL, LPBYTE( pszValueData ), &nSize );
			strValueData = pszValueData;
		}
	}
	
	VERIFY( ERROR_SUCCESS == ::RegCloseKey( hkOperatorConsole ) );

	return nResult;

}	// End GetConsoleIDEx()

Kevin

Re: Issue with strcpy

capricious_00118-Jun-06 23:36

capricious_001

18-Jun-06 23:36

There isnt any other way? Because there is a lot of code I have to change if I change the type of that one variable. I'd prefer keeping value as a LPSTR type.

Re: Issue with strcpy

Kevin McFarlane18-Jun-06 23:57

Kevin McFarlane

18-Jun-06 23:57

Well, in that case, as Laxman says, you need to carefully check the sizes of your source and destination buffers.

For future code though I recommend using string objects (string or CString) instead of C-style strings. You'll have fewer problems of this sort.

Kevin

Re: Issue with strcpy

Weiye Chen18-Jun-06 22:58

Weiye Chen

18-Jun-06 22:58

Is there really a need to pass by reference cos i think it can work without it.

Re: Issue with strcpy

_AnsHUMAN_ 18-Jun-06 23:05

_AnsHUMAN_

18-Jun-06 23:05

It's a problem with RegQueryValue(IMHO). You are not opening the registry before modifying it.
Handle to an open key. The key must have been opened with the KEY_QUERY_VALUE access right.
This handle is returned by the RegCreateKeyEx or RegOpenKeyEx function, or it can be one of the following predefined keys:

HKEY_CLASSES_ROOT
HKEY_CURRENT_CONFIG
HKEY_CURRENT_USER
HKEY_LOCAL_MACHINE
HKEY_PERFORMANCE_DATA
HKEY_PERFORMANCE_NLSTEXT
HKEY_PERFORMANCE_TEXT
HKEY_USERS

Somethings seem HARD to do, until we know how to do them.
Wink | ;-)

_AnShUmAn_

Re: Issue with strcpy

capricious_00118-Jun-06 23:14

capricious_001

18-Jun-06 23:14

Ya I created a handle to the open key and all of that is fine (closed the handle appropriately etc). Its just with the strcpy that I'm having the problems with.

As well, either by passing via reference or returning LPSTR value, I am still receiving the same unhandled exception error. It still crashes when my program is loaded.

Re: Issue with strcpy [modified]

Weiye Chen18-Jun-06 23:49

Weiye Chen

18-Jun-06 23:49

I just did a test using your code(with some modifications in bold) except without the reference and it works fine.:

void somefunc()
{
   char cBuffer[400];
   retrieveLogFileLocation(cBuffer);
}

bool retrieveLogFileLocation(LPSTR value)
{
    char lszValue[255];
    HKEY hKey = HKEY_LOCAL_MACHINE;
    LONG returnStatus;
    DWORD dwType = REG_SZ;
    DWORD dwSize =255;
    bool success = true;

    RegQueryValueEx(hKey, "InstallationPath", NULL, &dwType, (LPBYTE)&lszValue, &dwSize);

    strcpy(value, lszValue);

    return true;
}

I set hKey just for testing purposes. It could be a problem with your key.

Last modified: Monday, June 19, 2006 4:57:58 AM --

Re: Issue with strcpy

David Crow19-Jun-06 2:54

David Crow

19-Jun-06 2:54

_AnShUmAn_ wrote:
You are not opening the registry before modifying it.

While it's true that the registry key must be opened prior to use, it's certainly not being modified.

"The largest fire starts but with the smallest spark." - David Crow

"Judge not by the eye but by the heart." - Native American Proverb

Re: Issue with strcpy

David Crow19-Jun-06 2:56

David Crow

19-Jun-06 2:56

capricious_001 wrote:
bool retrieveLogFileLocation(LPSTR& value){

What is the size of the variable that value refers to?

capricious_001 wrote:
char[255] lszValue;

What's this?

capricious_001 wrote:
RegQueryValueEx(hKey, "InstallationPath", NULL, &dwType, (LPBYTE)&lszValue, &dwSize);

What does RegQueryValueEx() return?

capricious_001 wrote:
strcpy(value, lszValue);

Use strncpy() instead.

"The largest fire starts but with the smallest spark." - David Crow

"Judge not by the eye but by the heart." - Native American Proverb

How to ShellExecute notepad.exe to show a CString?

Tcpip200518-Jun-06 22:28

Tcpip2005

18-Jun-06 22:28

How could I show a CString use notepad.exe without saving the string into a txt file?

Re: How to ShellExecute notepad.exe to show a CString?

Hamid_RT18-Jun-06 22:36

Hamid_RT

18-Jun-06 22:36

See

<br />
::ShellExecute(NULL,_T("open"),_T("notepad.exe"),NULL,NULL,SW_SHOWNORMAL);<br />
Sleep(150);<br />
<br />
HWND hNoteWnd=::FindWindow(_T("Notepad"),NULL);<br />
LPCTSTR MY;<br />
MY=_T("Check");<br />
<br />
CWnd* hEditWnd=FindWindowEx(hNoteWnd,NULL,_T("Edit"),NULL);<br />
::SendMessage(hEditWnd->m_hWnd,WM_SETTEXT,0,(LPARAM)MY);<br />
<br />

whitesky

Re: How to ShellExecute notepad.exe to show a CString?

David Crow19-Jun-06 2:58

David Crow

19-Jun-06 2:58

WhiteSky wrote:
Sleep(150);

HWND hNoteWnd=::FindWindow(_T("Notepad"),NULL);

Use ShellExecuteEx() and these two statements can be avoided.

"The largest fire starts but with the smallest spark." - David Crow

"Judge not by the eye but by the heart." - Native American Proverb

Re: How to ShellExecute notepad.exe to show a CString?

Hamid_RT19-Jun-06 4:18

Hamid_RT

19-Jun-06 4:18

Thank you Mr DavidCrow for information Smile | :)

whitesky

Re: How to ShellExecute notepad.exe to show a CString?

Viorel.18-Jun-06 22:38

Viorel.

18-Jun-06 22:38

Maybe a previous discussion[^] can help.

a problem in visual C++

mt_samiei18-Jun-06 22:09

mt_samiei

18-Jun-06 22:09

Hi guys

I get following error when running my program.

Run-Time Check Failure #2 - Stack around the variable 'Temp' was corrupted.

where 'Temp' is a pointer to a class.

Does anyone know what the source of this run time error is ?

regards
Mahdi

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