From: Tutor <tutor-bounces+sjeik_appie=hotmail....@python.org> on behalf of
Mark Lawrence via Tutor <tutor@python.org>
Sent: Monday, September 25, 2017 4:19 PM
To: tutor@python.org
Subject: Re: [Tutor] logging to cmd.exe
On 25/09/2017 14:20, Albert-Jan Roskam wrote:
> Hi,
>
>
> With Python 3.5 under Windows I am using the logging module to log messages
> to stdout (and to a file), but this occasionally causes logging errors
> because some characters cannot be represented in the codepage used by cmd.exe
> (cp850, aka OEM codepage, I think). What is the best way to prevent this
> from happening? The program runs fine, but the error is distracting. I know I
> can use s.encode(sys.stdout.encoding, 'replace') and log that, but this is
> ugly and tedious to do when there are many log messages. I also don't
> understand why %r (instead of %s) still causes an error. I thought that the
> character representation uses only ascii characters?!
>
>
> import logging
> import sys
>
> assert sys.version_info.major > 2
> logging.basicConfig(filename="d:/log.txt",
> level=logging.DEBUG,format='%(asctime)s %(message)s')
> handler = logging.StreamHandler(stream=sys.stdout)
> logger = logging.getLogger(__name__)
> logger.addHandler(handler)
>
> s = '\u20ac'
> logger.info("euro sign: %r", s)
>
>
>
> --- Logging error ---
> Traceback (most recent call last):
> File "c:\python3.5\lib\logging\__init__.py", line 982, in emit
> stream.write(msg)
> File "c:\python3.5\lib\encodings\cp850.py", line 19, in encode
> return codecs.charmap_encode(input,self.errors,encoding_map)[0]
> UnicodeEncodeError: 'charmap' codec can't encode character '\u20ac' in
> position 12: character maps to <undefined>
> Call stack:
> File "q:\temp\logcheck.py", line 10, in <module>
> logger.info("euro sign: %r", s)
> Message: 'euro sign: %r'
> Arguments: ('\u20ac',)
>
>
> Thanks in advance for your replies!
>
>
> Albert-Jan
>
Rather than change your code can you change the codepage with the chcp
command?
========> Good to keep in mind, but my objection would be similar to that with
specifying the PYTHONIOENCODING variable: one needs to change the environment
first before the script runs without errors.
C:\Users\Mark\Documents\MyPython>chcp
Active code page: 65001
========> Wow! cmd.exe can use cp65001 aka utf8??? I always thought 65001 was
not a 'real' codepage, even though some locales (e.g. Georgia) use it [1]. Why
does cmd.exe still use cp850?
[1] https://docs.moodle.org/dev/Table_of_locales
PS: sorry about the missing quote (>>) markers. Hotmail can't do this. Is Gmail
better?
_______________________________________________
Tutor maillist - Tutor@python.org
To unsubscribe or change subscription options:
https://mail.python.org/mailman/listinfo/tutor
