How to find out if process created with ShellExecuteEx owns a window?

Question

I'm using ShellExecuteEx to run external application:

SHELLEXECUTEINFO shExInfo = { 0 };
    shExInfo.cbSize = sizeof(shExInfo);
    shExInfo.fMask = SEE_MASK_NOCLOSEPROCESS;
    shExInfo.hwnd = 0;
    shExInfo.lpVerb = L"runas";                // Operation to perform
    shExInfo.lpFile = windowStringContainingAppPath.c_str();       // Application to start    
    shExInfo.lpParameters = windowStringContainingAppParameters.c_str();                  // Additional parameters
    shExInfo.lpDirectory = 0;
    shExInfo.nShow = SW_SHOW;
    shExInfo.hInstApp = 0;

    if(ShellExecuteEx(&shExInfo))
    {
        WaitForSingleObject(shExInfo.hProcess, INFINITE);

        DeleteFile(wsMesh3dx64Parameter.c_str());

        CloseHandle(shExInfo.hProcess);
    }

Everything works perfectly but there exist an unplanned behaviour of this external app that after closing its main window its process is still active. This prevents WaitForSingleObject(shExInfo.hProcess, INFINITE); from returning and I have to terminate the process manualy.

Instead I'm looking for a way to replace WaitForSingleObject(shExInfo.hProcess, INFINITE);with a loop that checks if external process owns a window and if not terminate it.

This is what I thought of but if there is a better way please point it out for me.

UPDATE:

Thanks to Robson answer I managed to do what I intended to:

struct Porcess_ID_HWND
{
    DWORD processID;
    HWND processhWnd;
};

BOOL CALLBACK EnumWindowsProc(HWND hWnd, LPARAM lParam)
{
    Porcess_ID_HWND*info = (Porcess_ID_HWND*)lParam;

    DWORD processID;
    GetWindowThreadProcessId(hWnd, &processID);

    if (processID == info->processID){
        info->processhWnd = hWnd;
        return FALSE;
    }

    return TRUE;
}

And my loop:

if(ShellExecuteEx(&shExInfo))
{
    DWORD dwProcessID = GetProcessId(shExInfo.hProcess);

    Porcess_ID_HWND info;
    info.processID = dwProcessID;
    // wait for window to appear
    do
    {
        info.processhWnd = NULL;
        EnumWindows(EnumWindowsProc, (LPARAM)&info);

    } while (!info.processhWnd);

    // wait for window to close
    do
    {
        info.processhWnd = NULL;
        EnumWindows(EnumWindowsProc, (LPARAM)&info);

    } while (info.processhWnd);

    //WaitForSingleObject(shExInfo.hProcess, INFINITE);

    DeleteFile(wsMesh3dx64Parameter.c_str());

    CloseHandle(shExInfo.hProcess);
}

score 3 · Accepted Answer · answered May 05 '15 at 11:28

found a good answer at http://forums.codeguru.com/showthread.php?392273-RESOLVED-How-to-get-window-s-HWND-from-it-s-process-handle

1)
HAVE: Process ID, NEED: Process handle
Solution: OpenProcess()

2)
HAVE: Process handle, NEED: Process ID
Solution: GetProcessId()

3)
HAVE: Window handle, NEED: Process ID
Solution: GetWindowThreadProcessId()

4)
HAVE: Window handle, NEED: Process handle
Solution: Use 3) and then 1)

5)
HAVE: Process ID, NEED: Window handle
Solution: EnumWindows(), then in the callback function do 3) and check if it matches your process ID.

6)
HAVE: Process handle, NEED: Window handle
Solution: 2) and then 5)

so you are in case 6. then if no window handle's process ID is matched with your shExInfo.hProcess's process ID then shExInfo.hProcess owns no window

How to find out if process created with ShellExecuteEx owns a window?

1 Answers1