On 30/06/13 10:51, Alan Gauld wrote:
On 29/06/13 16:00, Matt D wrote:
with tempfile.NamedTemporaryFile('a+t',) as tf:
self.logfile = tf
This could give problems.
with guarantees to close the file at the end of the block.
But you have assigned it to self.logfile.
So when the file is closed (and tempfile then deletes the
file on disk) your self.logfile points at... nothing?!
No, it points to a closed file object, which is perfectly legal. And in fact,
so does tf.
py> with tempfile.NamedTemporaryFile('a+t',) as tf:
... pass
...
py> tf
<closed file '<fdopen>', mode 'a+t' at 0xb7f9cd30>
A file object is just a bunch of data such as file name, file mode, pointer to a file,
etc. When you close the file, the pointer becomes invalid but the rest of the file object
doesn't disappear, it just gets flagged as "closed".
ValueError: I/O operation on closed file
I have no idea what that means.
It means that Matt is trying to do something input/output related on a closed
file that can only be done on an open file, like write to it.
I haven't read this entire thread, but the bits I have read lead me to think
that Matt has tangled himself up in a total confused mess. It's *not this hard*
to write status messages to a log file, the log module does all the work. Can
anyone who has read the thread summarise what Matt is attempting to do?
--
Steven
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