[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[swgmma]

swgmma  added the comment:

Just squashed all the commits.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[swgmma]

Change by swgmma :


--
versions: +Python 3.11 -Python 3.8

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[swgmma]

swgmma  added the comment:

Anything else left to do?

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[Eryk Sun]

Eryk Sun  added the comment:

Here's an example test that calls WinAPI GetConsoleWindow() and 
IsWindowVisble() in a child process.

if mswindows:
try:
import ctypes
except ImportError:
ctypes = None

# added in Win32ProcessTestCase
def test_force_hide(self):
if ctypes:
script = textwrap.dedent(r'''
import sys, ctypes
GetConsoleWindow = ctypes.WinDLL('kernel32').GetConsoleWindow
IsWindowVisible = ctypes.WinDLL('user32').IsWindowVisible
sys.exit(IsWindowVisible(GetConsoleWindow()))
''')
else:
script = 'import sys; sys.exit(0)'
rc = subprocess.call([sys.executable, '-c', script], force_hide=True)
self.assertEqual(rc, 0)

This test will work reliably even if the user has Windows Terminal set as the 
default terminal (available with recent builds of Windows and Windows Terminal 
Preview). The proxy does not hand off to Windows Terminal if the STARTUPINFO 
wShowWindow is SW_HIDE or SW_SHOWMINIMIZED, or if the process is created with 
the CREATE_NO_WINDOW flag. In these cases, it just creates a system conhost.exe 
session.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[swgmma]

swgmma  added the comment:

Thanks all for the guidance. Have gone back to the original `force_hide` with 
the suggested documentation.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[Eryk Sun]

Eryk Sun  added the comment:

> There's nothing gained by complicating this API with more options.

Yes, both options is too much. I suggested force_hide_console as an alternative 
to force_hide, not for both to be implemented. It would be the same as 
CreateNoWindow in .NET ProcessStartInfo [1], but ProcessStartInfo also has 
WindowStyle, and one or the other is ignored depending on the value of 
UseShellExecute. I see a lot of confusion online regarding these .NET 
ProcessStartInfo properties, which is something I'd like to avoid.

A benefit of force_hide based on wShowWindow=SW_HIDE is feature parity with 
ShellExecuteExW(), if subprocess ever supports the shell API. ShellExecuteExW() 
does not support CREATE_NO_WINDOW, but it supports a show-window command and 
CREATE_NEW_CONSOLE (i.e. the inverse of SEE_MASK_NO_CONSOLE).

---
[1] 
https://docs.microsoft.com/en-us/dotnet/api/system.diagnostics.processstartinfo?view=net-5.0

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[Steve Dower]

Steve Dower  added the comment:

There's nothing gained by complicating this API with more options.

Document it as "Passing *force_hide* as True attempts to start the application 
without creating or showing any windows. Some applications may ignore this 
request, and applications that are hidden often cannot be used or exited by 
users."

We don't have to specify all the nuances here, especially since we may come up 
with a more reliable way to do this in the future. Specifying too much detail 
in the documentation will prevent us from improving it without breaking stuff.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[swgmma]

swgmma  added the comment:

What if we change `force_hide` from True/False to something like "off" | 
"console" | "all" (defaulting to "off")?

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[Eryk Sun]

Eryk Sun  added the comment:

If only force_hide is implemented, based on `wShowWindow=SW_HIDE`, please 
ensure that it's clearly documented that this option hides the main window 
(i.e. first top-level window) of any application that doesn't bypass the 
default behavior of the window manager.

This means a script can't simply use `force_hide=True` universally when running 
arbitrary commands, since hiding the main window of a GUI app is probably 
undesired behavior. If it's unknown in advance whether an executable is a 
console or GUI app, it can be determined via SHGetFileInfoW(). For example:

import ctypes
shell32 = ctypes.WinDLL('shell32', use_last_error=True)
SHGFI_EXETYPE = 0x2000

def is_gui_exe(path):
result = shell32.SHGetFileInfoW(path, 0, None, 0, SHGFI_EXETYPE)
# the high word is non-zero for a GUI app
return (result >> 16) > 0

>>> is_gui_exe(r'C:\Windows\pyw.exe')
True
>>> is_gui_exe(r'C:\Windows\py.exe')
False

Regarding the effect of wShowWindow:

If the STARTUPINFO record defines wShowWindow, the value gets used as the 
normal show command for the first top-level window that's shown in the process. 
In particular, it overrides the first use (and only the first use) of the 
commands SW_SHOW, SW_SHOWNORMAL, and SW_SHOWDEFAULT (yes, only the first use of 
the latter; the documentation is wrong). This affects showing the first 
top-level window regardless of whether it's explicit via ShowWindow() or 
implicit via the WS_VISIBLE window style. For the latter, the implicit command 
is SW_SHOW, which one can override in the CreateWindowW() call by passing 
x=CW_USEDEFAULT and y as the show command to use. 

To completely ignore the STARTUPINFO wShowWindow value for the main window, an 
application can use an initial show command that wShowWindow doesn't override, 
such as SW_HIDE, SW_RESTORE (behaves like SW_SHOWNORMAL on first use), 
SW_MINIMIZE, or SW_MAXIMIZE. For example, for the first command use 
ShowWindow(hwnd, SW_HIDE). Subsequently calling ShowWindow(hwnd, SW_SHOWNORMAL) 
will show the window normally (i.e. active and restored) instead of using the 
STARTUPINFO wShowWindow command.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[Steve Dower]

Steve Dower  added the comment:

I'd rather only have one force_hide option that does its best to hide 
everything.

Yes, it's probably unintuitive for GUI apps, it might even be maliciously 
misused, but it does have occasional legitimate uses. And besides, an app can 
easily ignore SW_HIDE if it wants.

Bear in mind that the test suite should (mostly) operate without ctypes. So if 
you use ctypes to verify the test, make it a separate test that skips if ctypes 
cannot be imported, and have a test that runs it without verifying the window 
is actually hidden. That way we always at least _run_ the code, even if we only 
(usually) verify that it's actually hiding the window.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[Eryk Sun]

Eryk Sun  added the comment:

> is it feasible to just have one option that handles all cases?

I'm in favor of whatever has broad support and is least surprising for users. I 
like CREATE_NO_WINDOW, which is restricted to console applications. The 
alternative is hiding the window, like what we do with shell=True. But the new 
option would also hide the main window of many GUI apps, which may come as a 
surprise and is hardly ever desired behavior.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[swgmma]

swgmma  added the comment:

For users who simply want to hide a process' window and do not have intimate 
knowledge of how the window is created by Windows, is it feasible to just have 
one option that handles all cases? Or do we have to implement both `force_hide` 
and `force_hide_console` and let users figure out which to use from the docs?

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[Eryk Sun]

Eryk Sun  added the comment:

> What is the most trivial way to test it's behaviour?

With CREATE_NO_WINDOW, the child process is attached to a console that has no 
window. Thus calling GetConsoleWindow() in the child returns NULL without an 
error. OTOH, if the child has no console (e.g. DETACHED_PROCESS or executing 
"pythonw.exe"), then GetConsoleWindow() returns NULL with the last error set to 
ERROR_INVALID_HANDLE (6). For example:

script = r'''
import sys
import ctypes
kernel32 = ctypes.WinDLL('kernel32', use_last_error=True)
kernel32.GetConsoleWindow.restype = ctypes.c_void_p
ctypes.set_last_error(0)
result = kernel32.GetConsoleWindow()
status = bool(result or ctypes.get_last_error())
sys.exit(status)
'''
args = [sys.executable, '-c', script]

The child's exit status will be 0 if CREATE_NO_WINDOW works as expected. 
Otherwise the exit status will be 1.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[swgmma]

swgmma  added the comment:

Just added a commit implementing `force_hide_console`.

What is the most trivial way to test it's behaviour?

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[Eryk Sun]

Eryk Sun  added the comment:

I was intending force_no_window as an alternative to adding force_hide, since 
CREATE_NO_WINDOW only affects console applications. Maybe a better name is 
force_hide_console.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[swgmma]

swgmma  added the comment:

I implemented your first suggestion for `force_hide`.

Should we add your `force_no_window` suggestion as well?

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[Eryk Sun]

Eryk Sun  added the comment:

The force_hide option could also force the use of a new hidden window, even if 
the current process has a console. That way the output is always hidden. For 
example:

if force_hide or shell:
if force_hide and not (creationflags & _winapi.DETACHED_PROCESS):
creationflags |= _winapi.CREATE_NEW_CONSOLE
startupinfo.dwFlags |= _winapi.STARTF_USESHOWWINDOW
startupinfo.wShowWindow = _winapi.SW_HIDE

One can also use CREATE_NO_WINDOW to create a console that has no window, as 
opposed to a hidden window. For example:

if force_no_window:
if creationflags & _winapi.CREATE_NEW_CONSOLE:
raise ValueError('force_no_window cannot be used with '
 'CREATE_NEW_CONSOLE')
creationflags |= _winapi.CREATE_NO_WINDOW

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[Steve Dower]

Steve Dower  added the comment:

That 'force_hide' in the NEWS shouldn't have single backticks. Make them 
``double``, or the docs won't compile.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[Steve Dower]

Steve Dower  added the comment:

Had a look. The change looks fine, just needs a NEWS entry, which I suggested 
as:

Adds new `force_hide` argument to :mod:`subprocess` functions. This passes 
``SW_HIDE`` to the new process, which most applications will use to not display 
any window even if they normally would.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[swgmma]

swgmma  added the comment:

Ping in case anyone from the windows team is available to review the PR

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[swgmma]

Change by swgmma :


--
pull_requests:  -18362

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[swgmma]

Change by swgmma :


--
pull_requests: +18362
pull_request: https://github.com/python/cpython/pull/18719

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[swgmma]

Change by swgmma :


--
keywords: +patch
pull_requests: +18361
stage: needs patch -> patch review
pull_request: https://github.com/python/cpython/pull/19014

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[swgmma]

swgmma  added the comment:

> Try running that script with pythonw.exe instead.

That did the trick. Confirmed that the changes are working as intended.

Running the test script posted earlier and adding the new `force_hide` kwarg to 
the subprocess call:

With `force_hide=False`, a command prompt window pops up.
With `force_hide=True`, no command prompt window pops up.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[Steve Dower]

Steve Dower  added the comment:

It'll have to be a program that cannot inherit the active console. Ffmpeg 
normally can, but running the first script with pythonw will make sure there is 
no console to inherit, and a new one will pop up for a regular Python process.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[Philip Lee]

Philip Lee  added the comment:

To reproduce the reported issue, one could also test with ffmpeg.exe

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[Steve Dower]

Steve Dower  added the comment:

Try running that script with pythonw.exe instead.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[swgmma]

swgmma  added the comment:

Sorry, perhaps I did not word it clearly. Indeed the code to implement this 
looks trivial, however the part I am having trouble with is reproducing the 
reported issue in the first place.

For example, running the attached file from a command prompt (`python test.py`) 
does not result in any additional windows popping up.

Either my test case is wrong or there is something else going on.

--
Added file: https://bugs.python.org/file48938/test.py

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[Steve Dower]

Steve Dower  added the comment:

If you use subprocess to launch any process that is marked SUBSYSTEM_CONSOLE, 
Windows will create a new console for it. For example, "python.exe" is such a 
process.

Eryk's answer in the very first StackOverflow link shows how to create a 
STARTUPINFO parameter with the correct settings. We just want to add a Boolean 
argument to subprocess.Popen.__init__() that can add that setting automatically.

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[swgmma]

swgmma  added the comment:

I would like to pick up work on this (have started at link below), however I 
would like some help:

For testing purposes, could someone please provide a minimum working example of 
using subprocess that causes a command prompt to pop up?

I have not been able to reproduce it (using Python 3.7), though I vaguely 
remember encountering it in the past.

https://github.com/ammgws/cpython/commit/03b9dac9205b9090dd67170427d887a9952345d3

--

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[swgmma]

Change by swgmma :


--
nosy: +swgmma

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[Steve Dower]

Steve Dower  added the comment:

Looks like it's available.

It will be a new subprocess option to not create a new window. The underlying 
issue is that some applications always request a console, and if your own 
application doesn't have one then Windows will create it. Normally you would 
fix this in the target application, but we can offer an option to try and force 
any new windows to be hidden (though as Eryk points out, it may cause 
unexpected behaviour and so should not be the default).

--
versions: +Python 3.8 -Python 3.7

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[neel patel]

neel patel  added the comment:

Can I work on this? I'm not sure of it's status, though.

--
nosy: +ohno

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[Jeffrey Rackauckas]

Changes by Jeffrey Rackauckas :


--
pull_requests: +3046

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[Eryk Sun]

Eryk Sun added the comment:

Hiding the console is required often enough that a keyword-only parameter for 
this would be useful. Other platforms could simply ignore it, in contrast to 
writing platform-dependent code that passes startupinfo. Note that this option 
would also hide the window of GUI programs that do not (intentionally) ignore 
SW_HIDE, such as notepad.

--
components: +Windows
keywords: +easy
nosy: +eryksun, paul.moore, steve.dower, tim.golden, zach.ware
stage:  -> needs patch
versions: +Python 3.7

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue30082] hide command prompt when using subprocess.Popen with shell=False on Windows

[Philip Lee]

New submission from Philip Lee:

First, It is nearly useless for the command prompt to pop up during  the 
running time of subprocess.Popen with shell=False.
Second, the popping up command prompt would interrupt users and do bad to user 
experience of GUI applications.
Third, I found QProcess within Qt won't pop up the command prompt  in using.

It would be convenient to add an argument to suppress the command prompt from 
popping up when using subprocess.Popen with shell=False on Windows, many users 
are missing the feature and these are many similar feature request questions 
like the following 
http://stackoverflow.com/questions/7006238/how-do-i-hide-the-console-when-i-use-os-system-or-subprocess-call
http://stackoverflow.com/questions/1765078/how-to-avoid-console-window-with-pyw-file-containing-os-system-call/12964900#12964900
http://stackoverflow.com/questions/1016384/cross-platform-subprocess-with-hidden-window

--
components: Library (Lib)
messages: 291760
nosy: iMath
priority: normal
severity: normal
status: open
title: hide command prompt when using subprocess.Popen with shell=False on 
Windows
type: enhancement

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com