throws me an error, directory or path not found... but actually it does exists...

Are you sure?

$ cat 668658.pl
use strict;
use warnings;
use Data::Dumper;

sub f {
  my ($first, $second, $third) = @_;
  print "first:" . Dumper($first) . "\n";
  print "second:" . Dumper($second) . "\n";
  print "third:" . Dumper($third) . "\n";
}

my @arr = qw ( one two three );

f('@arr');
f(@arr);
__END__
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$ perl 668658.pl
first:$VAR1 = '@arr';
second:$VAR1 = undef;
third:$VAR1 = undef;
first:$VAR1 = 'one';
second:$VAR1 = 'two';
third:$VAR1 = 'three';
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