Python for Windows reports wrong local time when run under Cygwin on Europe/Moscow TZ
Tue Jun 8 13:30:17 GMT 2021
On 08.06.2021 16:04, L A Walsh wrote:
> On 2021/06/08 05:28, Mike Kaganski wrote:
>> No, I report a problem that a native program runs incorrectly *under
>> Cygwin*, because Cygwin is indeed part of the picture.
> The problem is in the MS-Win term program. If you report
> it to them and tell them it only misbehaves when you have a 3rd
> party app injecting "dll's" (libraries) into the MS-program, they
> will _likely_ tell you that they can't support every 3rd party
> program that injects libraries into MS programs, and they can only
> support you running it without the 3rd party programs.
First of all - please stop telling me that I required support. I didn't
demand anything, and was asking *in the hope*, but without any wrong
expectations that anyone owes anything here. I never claimed that
someone must support my use case - so please, please stop answering what
wasn't said. I am a free software developer, working on LibreOffice
project; I know what free software is, and what mailing list is. That
they don't support something doesn't mean it's inappropriate to ask with
a hope, a question that could be *possibly* answered, and which answer
could happen to be helpful also to others.
> Just like cygwin devs have noticed that various
> other programs (see
> BLODA:https://cygwin.com/faq/faq.html#faq.using.bloda )
> are known for causing problems in cygwin. The cygwin devs can't
> support all the 3rd party programs that interfere.
>> and being not a prophet, I can't know in advance if the actual bug
>> lies in Windows, in Python, or in Cygwin interaction with them.
> As I said before, python is probably picking up time-zone
> changes from _both_ cygwin and windows. The workaround is to use
> the appropriate version of python with the correct OS. Cygwin is
> an OS emulation, Win10 is another OS. They both have versions of
> python designed for them. If MS thought the cygwin version of python
> was good enough for every purpose, they wouldn't have issued their
> own version.
MS didn't. The native Windows builds of Python weren't from MS - they
were from LibreOffice and from Python Software Foundation, as described
in the initial mail (and at the sites linked there).
> You might ask on a python list if anyone else has experienced
> something similar with python or any other program. I'm fairly sure
> that neither MS nor cygwin design their OS with python in mind and
> that it is python that is interacting funny when running under some
> merge of both. Have you asked the python people about this problem?
> What did they suggest?
I will ask at Python, of course. I didn't yet, because I didn't want to
cross-post same question to many places, and am waiting until it's clear
that I need to ask there, not here.
>> And I assume that Cygwin is not declaring that its users "must never
>> run native applications from Cygwin", so I find that passage above
>> inappropriate and off-topic.
> Just because they don't tell you to never run linux apps
> directly in cygwin doesn't mean they support it if you insist on
> trying. Most devs won't tell you all the things you can't do, because
> that list is endless. That certainly doesn't suggest that they would
> support all the things that don't work.
>>> Though as to why -- likely the windows version is getting time zone
>>> clues + correction from BOTH cygwin and Windows, like it's told its
>>> in a TZ that is at 1 time, while Windows feeds it other data that
>>> says it is 2 hours off from the default.
>> Maybe. It's OK if no one here knows the reason - I of course don't
>> expect anyone here obliged to give an answer. My question was
>> intended to ask if someone (e.g., a Cygwin dev) somehow can see the
>> problem from their expertise, and - maybe - even know how to fix it.
>> Maybe there's some technique how to workaround this problem - and
>> even if it's not a Cygwin's bug, it still could be useful for Cygwin
>> users, hence still the post to the list, accompanied by someone's
>> workaround, would be reasonable and useful.
> When you say you run the Win python on cygwin, what do you
I mean "start Cygwin terminal - either C:\cygwin64\bin\mintty.exe, or
C:\cygwin64\Cygwin.bat; then start Python using a command line as
provided in the initial mail - I have provided there a full command line
with the path".
> ... I just ran python from windows (not the same version you
> have, but an old one python2.7. I ran it from bash, but the resulting
> python doesn't have any cygwin libraries loaded -- that tells me that
> python is looking at some absolute paths and the environment and picking
> up both -- it's a MS-python "bug".
> Look in its environment and remove any thing for timezone and try that.
I will try without TZ.
> Or look in your path and make sure there are no cygwin directories
> in the path that your win-python is using. I'm pretty sure that
> will solve your problem.
> FWIW, here is a list of what python running from 'bash.exe' from
> cygwin has loaded -- and none of it is from cygwin:
> /prog/Sysinternals/cmd/exe> Listdlls python
Indeed there's no Cygwin's DLLs reported.
More information about the Cygwin