Unable to use imported subprocess module

[s1113950]

I've even tried using subprocess32 as a replacement module, but no matter what I do the subprocess module shows up as empty somehow:

[INFO   ] [Kivy        ] v1.10.1
[INFO   ] [Python      ] v3.7.1 (default, Feb  4 2019, 20:11:34) 
[Clang 10.0.0 (clang-1000.11.45.5)]
{'__name__': 'subprocess', '__doc__': None, '__package__': None, '__loader__': None, '__spec__': None}
 Traceback (most recent call last):
   File "/Users/robertso/kivy-ios/piles-ios/YourApp/main.py", line 7, in <module>
 AttributeError: module 'subprocess' has no attribute '__file__'

it exists but doesn't contain anything inside of it.

Here are the files related to subprocess in my kivy-ios app; I've checked them out and the subprocess module appears to exist:

(venv) robertso@robertso-mac02:~/kivy-ios$ find . -name "*subprocess*"
./dist/hostpython3/lib/python3.7/lib-dynload/_posixsubprocess.cpython-37m-darwin.so
./dist/hostpython3/lib/python3.7/test/__pycache__/test_subprocess.cpython-37.opt-2.pyc
./dist/hostpython3/lib/python3.7/test/__pycache__/test_subprocess.cpython-37.opt-1.pyc
./dist/hostpython3/lib/python3.7/test/__pycache__/test_subprocess.cpython-37.pyc
./dist/hostpython3/lib/python3.7/test/test_subprocess.py
./dist/hostpython3/lib/python3.7/test/test_asyncio/__pycache__/test_subprocess.cpython-37.opt-2.pyc
./dist/hostpython3/lib/python3.7/test/test_asyncio/__pycache__/test_subprocess.cpython-37.opt-1.pyc
./dist/hostpython3/lib/python3.7/test/test_asyncio/__pycache__/test_subprocess.cpython-37.pyc
./dist/hostpython3/lib/python3.7/test/test_asyncio/test_subprocess.py
./dist/hostpython3/lib/python3.7/test/subprocessdata
./dist/hostpython3/lib/python3.7/subprocess.pyc
./dist/hostpython3/lib/python3.7/subprocess.py
./dist/hostpython3/lib/python3.7/__pycache__/subprocess.cpython-37.pyc
./dist/hostpython3/lib/python3.7/__pycache__/subprocess.cpython-37.opt-2.pyc
./dist/hostpython3/lib/python3.7/__pycache__/subprocess.cpython-37.opt-1.pyc
./dist/hostpython3/lib/python3.7/asyncio/subprocess.py
./dist/hostpython3/lib/python3.7/asyncio/__pycache__/base_subprocess.cpython-37.opt-1.pyc
./dist/hostpython3/lib/python3.7/asyncio/__pycache__/base_subprocess.cpython-37.opt-2.pyc
./dist/hostpython3/lib/python3.7/asyncio/__pycache__/subprocess.cpython-37.pyc
./dist/hostpython3/lib/python3.7/asyncio/__pycache__/base_subprocess.cpython-37.pyc
./dist/hostpython3/lib/python3.7/asyncio/__pycache__/subprocess.cpython-37.opt-2.pyc
./dist/hostpython3/lib/python3.7/asyncio/__pycache__/subprocess.cpython-37.opt-1.pyc
./dist/hostpython3/lib/python3.7/asyncio/base_subprocess.py
./dist/root/python3/lib/python3.7/site-packages/subprocess32-3.5.3.dist-info
./dist/root/python3/lib/python3.7/site-packages/future/moves/subprocess.py
./dist/root/python3/lib/python3.7/site-packages/future/moves/__pycache__/subprocess.cpython-37.opt-2.pyc
./venv/lib/python3.7/site-packages/future/moves/subprocess.py
./venv/lib/python3.7/site-packages/future/moves/__pycache__/subprocess.cpython-37.pyc
./build/hostpython3/x86_64/Python-3.7.1/Lib/test/test_subprocess.py
./build/hostpython3/x86_64/Python-3.7.1/Lib/test/test_asyncio/test_subprocess.py
./build/hostpython3/x86_64/Python-3.7.1/Lib/test/subprocessdata
./build/hostpython3/x86_64/Python-3.7.1/Lib/subprocess.py
./build/hostpython3/x86_64/Python-3.7.1/Lib/__pycache__/subprocess.cpython-37.pyc
./build/hostpython3/x86_64/Python-3.7.1/Lib/asyncio/subprocess.py
./build/hostpython3/x86_64/Python-3.7.1/Lib/asyncio/__pycache__/subprocess.cpython-37.pyc
./build/hostpython3/x86_64/Python-3.7.1/Lib/asyncio/__pycache__/base_subprocess.cpython-37.pyc
./build/hostpython3/x86_64/Python-3.7.1/Lib/asyncio/base_subprocess.py
./build/hostpython3/x86_64/Python-3.7.1/Doc/library/subprocess.rst
./build/hostpython3/x86_64/Python-3.7.1/Doc/library/asyncio-subprocess.rst
./build/hostpython3/x86_64/Python-3.7.1/build/temp.macosx-10.14-x86_64-3.7/Users/robertso/kivy-ios/build/hostpython3/x86_64/Python-3.7.1/Modules/_posixsubprocess.o
./build/hostpython3/x86_64/Python-3.7.1/build/lib.macosx-10.14-x86_64-3.7/_posixsubprocess.cpython-37m-darwin.so
./build/hostpython3/x86_64/Python-3.7.1/Modules/_posixsubprocess.c
./build/python3/arm64/Python-3.7.1/Lib/test/test_subprocess.py
./build/python3/arm64/Python-3.7.1/Lib/test/test_asyncio/test_subprocess.py
./build/python3/arm64/Python-3.7.1/Lib/test/subprocessdata
./build/python3/arm64/Python-3.7.1/Lib/subprocess.py
./build/python3/arm64/Python-3.7.1/Lib/asyncio/subprocess.py
./build/python3/arm64/Python-3.7.1/Lib/asyncio/base_subprocess.py
./build/python3/arm64/Python-3.7.1/Doc/library/subprocess.rst
./build/python3/arm64/Python-3.7.1/Doc/library/asyncio-subprocess.rst
./build/python3/arm64/Python-3.7.1/build/temp.ios-aarch64-3.7/Users/robertso/kivy-ios/build/python3/arm64/Python-3.7.1/Modules/_posixsubprocess.o
./build/python3/arm64/Python-3.7.1/Modules/_posixsubprocess.c
./build/python3/x86_64/Python-3.7.1/Lib/test/test_subprocess.py
./build/python3/x86_64/Python-3.7.1/Lib/test/test_asyncio/test_subprocess.py
./build/python3/x86_64/Python-3.7.1/Lib/test/subprocessdata
./build/python3/x86_64/Python-3.7.1/Lib/subprocess.py
./build/python3/x86_64/Python-3.7.1/Lib/asyncio/subprocess.py
./build/python3/x86_64/Python-3.7.1/Lib/asyncio/base_subprocess.py
./build/python3/x86_64/Python-3.7.1/Doc/library/subprocess.rst
./build/python3/x86_64/Python-3.7.1/Doc/library/asyncio-subprocess.rst
./build/python3/x86_64/Python-3.7.1/build/temp.ios-x86_64-3.7/Users/robertso/kivy-ios/build/python3/x86_64/Python-3.7.1/Modules/_posixsubprocess.o
./build/python3/x86_64/Python-3.7.1/Modules/_posixsubprocess.c
./piles-ios/YourApp/__pycache__/subprocess.cpython-37.pyc

[s1113950]

I believe this is because of here: https://github.com/kivy/kivy-ios/blob/master/tools/templates/%7B%7B%20cookiecutter.project_name%20%7D%7D-ios/main.m#L158 does this mean that the subprocess module isn't designed to work with Kivy iOS apps? It works just fine when ran other ways.

[tito]

What do you mean by other ways?
I put that because it didn't worked at all, but can be required on some imports (i don't remember which one)

[s1113950]

It runs fine when run as python main.py for example, or when put on Android.

[Zen-CODE]

I'm pretty sure the multi-processing is not supported on iOS. I remember reading a more detailed article, but this link serves to confirm...
https://forum.omz-software.com/topic/4638/permission-error-with-multiprocessing-process

Multi-processing is something Apple deliberately tries to prevent. From the article below: "Despite iOS being a multitasking OS, it does not support multiple processes for one app."

https://medium.com/flawless-app-stories/basics-of-parallel-programming-with-swift-93fee8425287
[Updated] Gave wrong link above

[Zen-CODE]

I'm taking the liberty of closing this as it's not a kivy issue. This seems to be a limitation inherent to iOS. Please feel free to re-open if there is any evidence to the contrary.

Thanks

[tito]

Just a note, simply importing asyncio (what kivy does in master) was using subprocess.PIPE.

[s1113950]

I have a workaround for this:

# monkeypatching the things that asyncio needs
import subprocess
subprocess.PIPE = -1  # noqa
subprocess.STDOUT = -2  # noqa
subprocess.DEVNULL = -3  # noqa

I have this set right after my kivy.require statement at the top of my main.py file and things work fine for me. I'm using kivy v1.11.0.dev0, git-Unknown, 20190421 though, so not latest master.