On Wed, Nov 12, 2014 at 10:47 PM, Eric Mertens <emertens@gmail.com> wrote:
It's not vulnerable to the same issue because hClose can't block (as far as I know) because it can't be in use at the time that clean up is running.

This sounds unsafe to me. System file descriptors are per process, and there are at least three such that *must* be per process (stdin, stdout, stderr). And, while closing those isn't especially common, it can be and is done sometimes. Can you guarantee that the corresponding handle's not in use?

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