Python 3.8.5 Not Launching

[Eryk Sun]

On 10/2/20, Gertjan Klein <gklein at xs4all.nl> wrote:
> Eryk Sun wrote:
>
>> If .py files are associated with py.exe or python.exe, then running a
>> .py script either inherits or allocates a console and attaches to it.
>
> Is it possible to determine, from within Python, whether Python
> allocated or inherited the console?

If a console session isn't headless (i.e. it's not a pseudoconsole)
and has a window (i.e. not allocated with CREATE_NO_WINDOW), then the
effective owner of the window is initially the process that allocated
the console session, as long as it's still running and attached. For
example, with "python.exe" (not a launcher) executed from Explorer:

    >>> hwnd = win32console.GetConsoleWindow()
    >>> tid, pid = win32process.GetWindowThreadProcessId(hwnd)
    >>> pid == os.getpid()
    True

A problem is the case of a launcher such as "py.exe", or the
"python.exe" launcher used by venv virtual environments. A venv
launcher can be detected by comparing sys.executable with
sys._base_executable. For example, with a venv launcher executed from
Explorer:

    >>> hwnd = win32console.GetConsoleWindow()
    >>> tid, pid = win32process.GetWindowThreadProcessId(hwnd)

The current process doesn't own the console, but the parent does:

    >>> pid == os.getpid()
    False
    >>> pid == os.getppid()
    True

Check whether the parent is a venv launcher:

    >>> print(sys.executable)
    C:\Temp\env\test38\Scripts\python.exe
    >>> print(sys._base_executable)
    C:\Program Files\Python38\python.exe

Double check that the parent is the venv launcher:

    >>> access = win32con.PROCESS_QUERY_LIMITED_INFORMATION
    >>> hproc = win32api.OpenProcess(access, False, pid)
    >>> executable = win32process.GetModuleFileNameEx(hproc, None)
    >>> os.path.samefile(executable, sys.executable)
    True