Hi Marshall!
Thanks for your reply.

> File "locking" is a way for programs to cooperate if they choose to do so.
Only another instances of the same script have access to the file, so I think there will be no problem.

> I don't think that Version#1 works because I don't see an UNLOCK operation.
Actually, Version#1 worked over a year. I thought that close() operation unlocks the file. Isn't that correct?

> my $tempfile = "./tempfile".(rand()*9999);
> is not a good way for this. Ask the OS for a guaranteed
> unique temp file name. When you are finished with it, I would clean it up (delete it)
I guess rename() operation solves the problem by renaming/moving temp file into the original filename. But I'm not sure how does rename() interfere with flock and close(). Does it remove previously made lock, or overwritten file continues to be locked until I close() it?

In reply to Re^2: Trying to optimize reading/writing of large text files. by nikkimouse
in thread Trying to optimize reading/writing of large text files. by nikkimouse

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