Why do you need it? Most processes don't care about the name of a file they've already opened. The filehandle stays connected to it even if the file name changes: 
#!/usr/bin/perl
use warnings;
use strict;
use feature qw{ say };

open my $OUT, '>', '1' or die $!;

my $child = fork;
if ($child) {
    sleep 1;
    my %new_name = map +($_ => $_ + 1), 1 .. 8;
    for my $old (1 .. 8) {
        rename $old, $new_name{$old} or die $!;
        say "$old renamed to $new_name{$old}.";
        sleep 1;
    }
    exit
}

defined $child or die "Can't fork";
for (1 .. 10) {
    say {$OUT} $_;
    say "Printed: $_.";
    sleep 1;
}

[download]

map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]

In reply to Re: Easy way to check if a file is open needed. by choroba
in thread Easy way to check if a file is open needed. by Apt_Addiction

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