Well as far as I know there is no direct function or way to find processes using a file... so I wrote this, it could be bad code I dunno feel free to tell me, and also btw it should really only work on linux (or any other os that stores files open in /proc/pid/fd/file desc) 
use Linux::Fuser;

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Was this ugly mess from the year 2000: 
package File::Fuser;

use strict;
use vars qw( @ISA @EXPORT );
use File::Spec;
use Exporter;
@ISA = qw(Exporter);
@EXPORT = qw(fuser);

sub fuser { 
    my($file) = File::Spec->rel2abs($_[0]);
    my($f,@pids);
    foreach(glob("/proc/*")) { 
        if ($_ =~ /^\/proc\/\d+$/) { 
            foreach $f(glob("$_/fd/*")) { 
                if ((reverse(File::Spec->splitpath($f)))[0] > 3 && -l 
+$f) { 
                    if (readlink($f) eq $file) { 
                        push(@pids,(reverse(File::Spec->splitpath($_))
+)[0]);
                    }
                }
            }
        }
    }
    return((@pids)? @pids : -1);
}

1;

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In reply to Fuser under perl by lindex

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