C / C++ / MFC

9-Aug-02 4:07

How can I get the name of the program that have created a window given its HWND

David Viggiano9-Aug-02 4:17

9-Aug-02 4:17

Check out http://www.mooremvp.freeserve.co.uk/Win32/framed_tip038.htm

Slayders9-Aug-02 4:27

9-Aug-02 4:27

Thanks you.
It seems more difficult than I thought!!!

David Viggiano9-Aug-02 4:35

9-Aug-02 4:35

Yea it is. Getting the PID is not the problem, as you can see. Getting the process name from the PID is difficult.

But there is an easier solution if PSAPI.DLL is installed. By default it is there on W2K and XP, redistributable for NT is available. No support for 95/98/Me. Here is how I use it:

In my constructor I have something like

HINSTANCE hInst;

m_pfGetModuleBaseName = NULL;
m_pfEnumProcessModules = NULL;

hInst = LoadLibrary (_T("psapi.dll"));
if (hInst != NULL)
{
m_pfGetModuleBaseName = (GETMODULEBASENAME) GetProcAddress (hInst, _T("GetModuleBaseNameA"));
m_pfEnumProcessModules = (ENUMPROCESSMODULES)GetProcAddress (hInst, _T("EnumProcessModules"));
FreeLibrary (hInst);
}
}

Then I use it as follows

HANDLE hProc;
HMODULE ahMod[10];
DWORD dwNeeded;
BOOL bStatus = FALSE;
char szProcessName[80];

rStrProcessName = "";

if (m_pfEnumProcessModules == NULL || m_pfGetModuleBaseName == NULL)
return (FALSE);

// Need to get a handle to the process so we can query the modules
hProc = OpenProcess (PROCESS_QUERY_INFORMATION|PROCESS_VM_READ, FALSE, dwPID);
if (hProc)
{
// Get the first few modules. The .exe is always the first one.
if (m_pfEnumProcessModules (hProc, ahMod, sizeof(ahMod), &dwNeeded))
{
// Get the exe name. It is always the first module.
if (m_pfGetModuleBaseName (hProc, ahMod[0], szProcessName, sizeof(szProcessName)))
{
rStrProcessName = szProcessName;
bStatus = TRUE;
}
}
CloseHandle (hProc);
}
return (bStatus);
}

Slayders9-Aug-02 5:16

9-Aug-02 5:16

In the source code from the URL: The function RegQueryValueEx has as first parameter HKEY_PERFORMANCE_DATA but this key is only available for NT/2k/XP. How can I make this function works with 98/NT/2000/XP?

David Viggiano9-Aug-02 5:28

9-Aug-02 5:28

Ah the joys of enumerating process under the different versions of Windows. For 95/98 the best method is to use the ToolHelp API. See the example on MSDN under Process32First().

What we have done here is wrap all of the messy platform specific details into a class.

D

Slayders9-Aug-02 5:38

9-Aug-02 5:38

I've already seen it but it's written that it is running on Windows CE!!

When I try to compile the code from the URL the compiler doesn't know the structure PPERF_DATA_BLOCK, PPERF_OBJECT_TYPE, PPERF_INSTANCE_DEFINITION, PPERF_COUNTER_BLOCK and PPERF_COUNTER_DEFINITION. And I don't find it in the MSDN.

David Viggiano9-Aug-02 5:50

9-Aug-02 5:50

I'm not sure I understand your first sentence. Be careful with MSDN, there are usually two definitions when you search for something. One is for CE and one is for standard Win32. The ToolHelp API functions work under CE and 98 so you might have been looking at the CE example.

The PPERF_* structures are defined in WinPerf.h. The "PP" mean pointer to structure so if you take the first "P" off, you can see them in MSDN (look for PERF_DATA_BLOCK instead of PPERF_DATA_BLOCK).

Slayders9-Aug-02 6:03

9-Aug-02 6:03

I have been looking for "toolhelp" and there was only "toolhelp module" in the MSDN...

Now, it's working.

Thank you.

Slayders27-Aug-02 23:57