You can try os specific tools to see if a file is being used, for example fuser: 
open FILE, "sample";
system("fuser sample") or print "File not in use\n";
close FILE;
system("fuser sample") or print "File not in use\n";

[download]
Maybe Linux::Fuser from CPAN can help you.

In reply to Re: file locking by fauria
in thread file locking by Tomtom

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