[New-bugs-announce] [issue30460] file opened for updating cannot write after read

[Jeremy Kloth]

New submission from Jeremy Kloth:

Attempting to append to an existing file fails with no error set:

>>> import os, tempfile
>>> fd, fn = tempfile.mkstemp()
>>> os.write(fd, 'some text')
9
>>> os.close(fd)
>>> with open(fn, 'r+') as f:
...     f.read()
...     f.write('more text')
...     
'some text'
Traceback (most recent call last):
  File "<interactive input>", line 3, in <module>
IOError: [Errno 0] Error

(error 0 is defined as NO_ERROR)

----------
components: IO, Windows
messages: 294379
nosy: jkloth, paul.moore, steve.dower, tim.golden, zach.ware
priority: normal
severity: normal
status: open
title: file opened for updating cannot write after read
versions: Python 2.7

_______________________________________
Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue30460>
_______________________________________