GetWindowModuleFileNameW() get window's exe path fail with error 126? [duplicate] - winapi

Question

I try to get the name of executable name of all of my launched windows and my problem is that:
I use the method
UINT GetWindowModuleFileName(
HWND hwnd,
LPTSTR lpszFileName,
UINT cchFileNameMax);
And I don't understand why it doesn't work.
Data which I have about a window are: -HWND AND PROCESSID
The error is:
e.g:
HWND: 00170628
ProcessId: 2336
WindowTitle: C:\test.cpp - Notepad++
GetWindowModuleFileName(): C:\test.exe
HWND: 00172138
ProcessId: 2543
WindowTitle: Firefox
GetWindowModuleFileName(): C:\test.exe
HWND: 00120358
ProcessId: 2436
WindowTitle: Mozilla Thunderbird
GetWindowModuleFileName(): C:\test.exe
Note: test.exe is the name of my executable file, but it is not the fullpath of Notepad++... and it make this for Mozilla Thunderbird too... I don't understand why
I use the function like this:
char filenameBuffer[4000];
if (GetWindowModuleFileName(hWnd, filenameBuffer, 4000) > 0)
{
std::cout << "GetWindowModuleFileName(): " << filenameBuffer << std::endl;
}
Thank you for your response.

Answer 1

The GetWindowModuleFileName function works for windows in the current process only.
You have to do the following:
Retrieve the window's process with GetWindowThreadProcessId.
Open the process with PROCESS_QUERY_INFORMATION and PROCESS_VM_READ access rights using OpenProcess.
Use GetModuleFileNameEx on the process handle.
If you really want to obtain the name of the module with which the window is registered (as opposed to the process executable), you can obtain the module handle with GetWindowLongPtr with GWLP_HINSTANCE. The module handle can then be passed to the aforementioned GetModuleFileNameEx.
Example:
TCHAR buffer[MAX_PATH] = {0};
DWORD dwProcId = 0;
GetWindowThreadProcessId(hWnd, &dwProcId);
HANDLE hProc = OpenProcess(PROCESS_QUERY_INFORMATION | PROCESS_VM_READ , FALSE, dwProcId);
GetModuleFileName((HMODULE)hProc, buffer, MAX_PATH);
CloseHandle(hProc);

Answer 2

Aaah. I read the MSDN page at the bottom.
From http://support.microsoft.com/?id=228469 (archive.org link):
GetWindowModuleFileName and GetModuleFileName correctly retrieve information about windows and modules in the calling process. In Windows 95 and 98, they return information about windows and modules in other processes. However, in Windows NT 4.0 and Windows 2000, since module handles are no longer shared by all processes as they were on Windows 95 and 98, these APIs do not return information about windows and modules in other processes.
To get more information on Windows 2000, use the Process Status Helper set of APIs (known as PSAPI, see Psapi.h include file), available since Windows NT 4.0. APIs such as GetModuleFileNameEx and GetModuleBaseName offer equivalent functionality.
Try using GetModuleFileNameEx instead.

Answer 3

http://support.microsoft.com/?id=228469 (archive.org link)
The executive summary is, GetWindowModuleFileName() doesn't work for windows in other processes in NT-based Windows.
Instead, you can use QueryFullProcessImageName() once you have a handle to the process. You can get a handle to the process with OpenProcess(), which you can use once you have a process id. You can get the process id from the HWND by using GetWindowThreadProcessId()

Answer 4

This is an example of how get the name of executable that creates window, hope it can give you some ideas about:
while(true)
{
Sleep(250);//reduce cpu usage
CHAR __name[MAX_PATH];//name buffer
HWND hwnd;//window handle
DWORD pid;//process pid
hwnd=FindWindow(NULL,NULL);//find any window
PROCESSENTRY32 entry;//process structure containing info about processes
entry.dwSize=sizeof(PROCESSENTRY32);
HANDLE snapshot=CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS,0);//get processes
if(hwnd!=0)
{
GetWindowThreadProcessId(hwnd,&pid);//get found window pid
}
if (Process32First(snapshot,&entry)==TRUE)//start listing processes
{
while (Process32Next(snapshot,&entry)==TRUE)
{
if (stricmp(entry.szExeFile,"explorer.exe")==0)
{
if(pid!=entry.th32ProcessID)//if found window pid is explorers one, skip it
{
HANDLE hProcess=OpenProcess(PROCESS_ALL_ACCESS,FALSE,pid);//open processusing PROCESS_ALL_ACCESS to get handle
if(hProcess!=NULL)
{
GetModuleFileNameEx(hProcess,NULL,__name,MAX_PATH);//get executable path
cout<<"Found: "<<__name<<endl;
}
}
}
}
}
To use GetModuleFileNameEx() you probably will need to set linker settings to link library psapi. Also include psapi.h.