You mean by another program?
As far as i know, you can't.
But as a workaround, try to open the file exlusive, if it fails, it's probably opened.

In your own program, try using flock

"We all agree on the necessity of compromise. We just can't agree on when it's necessary to compromise." - Larry Wall.

In reply to Re: Check whether a file is open by jbrugger
in thread Check whether a file is open by knsridhar

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