File Name issue

[Mladen Gogala]

On Sun, 18 Oct 2020 21:00:18 +1300, dn wrote:

> On 18/10/2020 12:58, Mladen Gogala via Python-list wrote:
>> On Sat, 17 Oct 2020 22:51:11 +0000, Mladen Gogala wrote:
>>> On Sat, 17 Oct 2020 18:12:16 -0400, Steve wrote:
>>>
>>>> with open("HOURLYLOG.txt", 'r') as infile:
>>>> works but, when I rename the file, the line:
>>>> with open("HOURLY-LOG.txt", 'r') as infile:
>>>> does not.  The complaint is: Cannot Assign to operator
> 
>  >>> with open( "HOURLY-LOG.txt", "r" ) as f:
> ...     print( f.read() )
> ...
> yes
> ^^^ the entire contents of a magnificent test-file
> 
> NB:
> Python 3.8.5 (default, Aug 12 2020, 00:00:00)
> [GCC 10.2.1 20200723 (Red Hat 10.2.1-1)] on linux
> 
> 
>> BTW, I used this
>> cp /var/log/syslog ./in-file.log
>> #!/usr/bin/env python3
>> import io
>> with open("in-file.log","r") as infile:
>>      for line in infile:
>>          print(line)
>> I got a different error:
>> Traceback (most recent call last):
>>    File "./test.py", line 4, in <module>
>>      for line in infile:
>>    File "/usr/lib/python3.8/codecs.py", line 322, in decode
>>      (result, consumed) = self._buffer_decode(data, self.errors, final)
>> UnicodeDecodeError: 'utf-8' codec can't decode byte 0xd8 in position 
897:
>> invalid continuation byte
> 
> 
> @Mladen: is syslog a text file or binary format?

Hi!
Syslog is the system log. It's a text file. This only happens if I use 
infile as iterable. If I use readline, all is well:

#!/usr/bin/env python3
import io
with open("in-file.log","r") as infile:
    while True:
        line=infile.readline()
        if not line:
            break
        print(line)

I don't particularly like this idiom, but it works. That is probably a bug
in the utf-8 decoder on Ubuntu. It doesn't happen on my Fedora 32 VM. I 
haven't tried with infile.reconfigure(encoding=None)



-- 
Mladen Gogala
Database Consultant
http://mgogala.byethost5.com