This is only done for correctness sake; I don't see any way that it
would have caused a problem here. The jlog file escaped withOtherTmp
so another process could swoop in and delete it, but the file is only
used as a buffer for a list of filenames, and its handle gets rewound
and they're read back out, which will still work even if it's already
been deleted.
The only reason I didn't just pre-delete the file and keep the handle
open is I'm not sure that works on all OS's (eg Windows). If there was
a problem that this fixed it might involve an OS that doesn't support
deleting an open file or something like that.
