I have a small script that works where it copies a file from one Windows server to another. The destination file is always overwritten. Now I think I should check if the file I am copying from (sourceFile) is opened by someone and also check if the file I am copying to (destinationFile) is being open or being used. Here is my current copy command: 
Use File::Copy
...
copy($a,$b) ||  die "$!";

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Please advise how I can do this because I am not sure about opening it up and how flock works? 
open(INPUT, "<$a");  
@data = <INPUT>;        
close(INPUT);            
open (OUTPUT, ">$a"); 
flock(OUTPUT, 2);        
copy($a,$b) ||  die "$!";

[download]

In reply to Locking File for copy by Anonymous Monk

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