[Python-Dev] Can't have unbuffered text I/O in Python 3.0?

[Fabio Zadrozny]

It appears that this bug was already reported: http://bugs.python.org/issue4705

Any chance that it gets in the next 3.0.x bugfix release?

Just as a note, if I do: sys.stdout._line_buffering = True, it also
works, but doesn't seem right as it's accessing an internal attribute.

Note 2: the solution that said to pass 'wb' does not work, because I
need the output as text and not binary or text becomes garbled when
it's not ascii.

Thanks,

Fabio

On Fri, Dec 19, 2008 at 9:03 PM, Guido van Rossum <guido at python.org> wrote:
> Fror truly unbuffered text output you'd have to make changes to the
> io.TextIOWrapper class to flush after each write() call. That's an API
> change -- the constructor currently has a line_buffering option but no
> option for completely unbuffered mode. It would also require some
> changes to io.open() which currently rejects buffering=0 in text mode.
> All that suggests that it should wait until 3.1.
>
> However it might make sense to at least turn on line buffering when -u
> or PYTHONUNBUFFERED is given; that doesn't require API changes and so
> can be considered a bug fix.
>
> --Guido van Rossum (home page: http://www.python.org/~guido/)
>
>
>
> On Fri, Dec 19, 2008 at 2:47 PM, Antoine Pitrou <solipsis at pitrou.net> wrote:
>>
>>> Well, ``python -h`` still lists it.
>>
>> Precisely, it says:
>>
>> -u     : unbuffered binary stdout and stderr; also PYTHONUNBUFFERED=x
>>         see man page for details on internal buffering relating to '-u'
>>
>> Note the "binary". And indeed:
>>
>> ./python -u
>> Python 3.1a0 (py3k:67839M, Dec 18 2008, 17:56:54)
>> [GCC 4.3.2] on linux2
>> Type "help", "copyright", "credits" or "license" for more information.
>>>>> import sys
>>>>> sys.stdout.buffer.write(b"y")
>> y1
>>>>>
>>
>> I don't know what it would take to enable unbuffered text IO while keeping the
>> current TextIOWrapper implementation...
>>
>> Regards
>>
>> Antoine.
>>
>>
>> _______________________________________________
>> Python-Dev mailing list
>> Python-Dev at python.org
>> http://mail.python.org/mailman/listinfo/python-dev
>> Unsubscribe: http://mail.python.org/mailman/options/python-dev/guido%40python.org
>>
> _______________________________________________
> Python-Dev mailing list
> Python-Dev at python.org
> http://mail.python.org/mailman/listinfo/python-dev
> Unsubscribe: http://mail.python.org/mailman/options/python-dev/fabiofz%40gmail.com
>