[Win] Installation failure on Cygwin

[eabase]

Win

• { OS 8/10 }
• { psutil version: python3 -c "import psutil; print(psutil.version)" }
• { python version }

Bug description

Installation fails on Py3.8 under Cygwin. This is POSIX compatible and should work just as well as under WSL or any other *nix.

...

$ pip install psutil
Collecting psutil
  Downloading psutil-5.7.2.tar.gz (460 kB)
     |████████████████████████████████| 460 kB 528 kB/s
    ERROR: Command errored out with exit status 1:
     command: /usr/bin/python3.8.exe -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-geen0hz1/psutil/setup.py'"'"'; __file__='"'"'/tmp/pip-install-geen0hz1/psutil/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' egg_info --egg-base /tmp/pip-pip-egg-info-9xffagwt
         cwd: /tmp/pip-install-geen0hz1/psutil/
    Complete output (1 lines):
    platform cygwin is not supported
    ----------------------------------------
ERROR: Command errored out with exit status 1: python setup.py egg_info Check the logs for full command output.

Test results
{ output of python -c psutil.tests (failures only, not full result) }

---

UPDATE 2020-11-07

Apparently Cygwin is not supported as 'posix' nor 'nt', according to these related Issues:

• Cygwin Support #82 (Bump @embray )
• Please support cygwin! #1755
• https://github.com/giampaolo/psutil/issues?q=is%3Aissue+cygwin+is%3Aclosed

However, there were already some suggested PRs that was (never?) submitted.

[eabase]

Because in Cygwin:

# python -c "import os; print('\n'.join([os.name, os.sys.platform]));"
posix
cygwin

# python -c "import sys,os; print(os.uname()[0].split('-')[1]);"
6.3

IMPORTANT: ❗
If you have a native Windows Python installed in your windows path, you will get the wrong results above, as your Cygwin path will copy the windows path under normal settings. So either uninstall Python from Cygwin, or remove the Python item in the Windows path, from your Cygwin PATH (via ~/.bashrc, for example). You can test what is used with:

echo ${PATH}|tr ":" "\n"

ls -al `which python.exe`
ls -al `which python`

---

Looks like some initial support could be given by changing, replacing these lines:

• psutil/psutil/_common.py

  Lines 81 to 82 in 241f8ed

  	POSIX = os.name == "posix"
  	WINDOWS = os.name == "nt"

CYGWIN = os.sys.platform == "cygwin"

• psutil/scripts/winservices.py

  Line 40 in ecdaac3

  if os.name != 'nt':

if os.name != 'nt' and os.sys.platform != 'cygwin':

Then, in

• psutil/setup.py

  Lines 140 to 142 in 241f8ed

  	def get_winver():
  	maj, min = sys.getwindowsversion()[0:2]
  	return '0x0%s' % ((maj * 100) + min)

these lines could be added/replaced with:

def get_winver():
	return os.uname()[0].split('-')[1]

[giampaolo]

Cygwin is currently not supported. It's tracked in ticket 82 already.