Robert Xiao <nneon...@gmail.com> added the comment:
Could this be solvable if `closefd` were a writable attribute? Then we could do
file = None
try:
file = io.open(fd, ..., closefd=False)
file.closefd = True
except:
if file and not file.closefd:
os.close(fd)
raise
I believe this should be bulletproof - a KeyboardInterrupt can happen anywhere
in the `try` and we will not leak or double-close. Either file.closefd is set,
in which case `file` owns the fd and will close it eventually, or file.closefd
is not set in which case the fd needs to be manually closed, or file doesn't
exist (exception thrown in io.open or while assigning file), in which case the
fd still needs to be manually closed.
Of course, this can leak if a KeyboardInterrupt lands in the `except` - but
that's not something we can meaningfully deal with. The important thing is that
this shouldn't double-close if I analyzed it correctly.
This is a somewhat annoying pattern, though. I wonder if there's a nicer way to
implement it so we don't end up with this kind of boilerplate everywhere.
----------
_______________________________________
Python tracker <rep...@bugs.python.org>
<https://bugs.python.org/issue39318>
_______________________________________
_______________________________________________
Python-bugs-list mailing list
Unsubscribe:
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
