Apparent regression bug from Python 3.8 to 3.9: can't launch scripts using absolute Windows paths

Apparent regression bug from Python 3.8 to 3.9: can't launch scripts using absolute Windows paths

[Derek Foster]

Hi, folks.

I have been having problems with Python 3.9 packaged with Cygwin that I did not have with Python 3.8.

Specifically, I am seeing the following:

C:\example>copy con test.py
#!/usr/bin/env python3
print('hello')
^Z

C:\example>c:\cygwin64\bin\python3.8 test.py
hello

C:\example>c:\cygwin64\bin\python3.9 test.py
hello

C:\example>c:\cygwin64\bin\python3.8 C:\example\test.py
hello

C:\example>c:\cygwin64\bin\python3.9 C:\example\test.py
/usr/bin/python3.9: can't open file '/cygdrive/c/example/C:\example\test.py': [Errno 2] No such file or directory

There is an open bug on CPython for this ( https://github.com/python/cpython/issues/90907 ), but the people there seem to think it's something that the Cygwin folks should probably address, and I haven't been able to find a corresponding Cygwin bug.

What do I need to do to get this information to the appropriate team so that this bug can be fixed?

Thanks for any information!

Re: Apparent regression bug from Python 3.8 to 3.9: can't launch scripts using absolute Windows paths

[marco atzeri]

On Mon, Apr 25, 2022 at 8:59 AM Derek Foster  wrote:
>
> Hi, folks.
>
> I have been having problems with Python 3.9 packaged with Cygwin that I did not have with Python 3.8.
>
> Specifically, I am seeing the following:
>
> C:\example>copy con test.py
> #!/usr/bin/env python3
> print('hello')
> ^Z
>
> C:\example>c:\cygwin64\bin\python3.8 test.py
> hello
>
> C:\example>c:\cygwin64\bin\python3.9 test.py
> hello
>
> C:\example>c:\cygwin64\bin\python3.8 C:\example\test.py
> hello
>
> C:\example>c:\cygwin64\bin\python3.9 C:\example\test.py
> /usr/bin/python3.9: can't open file '/cygdrive/c/example/C:\example\test.py': [Errno 2] No such file or directory
>
> There is an open bug on CPython for this ( https://github.com/python/cpython/issues/90907 ), but the people there seem to think it's something that the Cygwin folks should probably address, and I haven't been able to find a corresponding Cygwin bug.
>
> What do I need to do to get this information to the appropriate team so that this bug can be fixed?

Neither of the two is a bug. The usage of Windows style path is not
guaranteed on any Cygwin package.
Some programs handle it other don't

Use "cygpath" to convert it.

There is nothing specific on Python patches for Cygwin to handle it.
More likely a upstream change disabled this "side" feature


> Thanks for any information!

Regards
Marco