##
use strict;
use warnings;
use Getopt::Long qw(GetOptions);
sub usage {
if (@_) {
my ($msg) = @_;
chomp($msg);
print(STDERR "$msg\n");
}
GetOptions(
'root=s' => \my $dir,
'out=s' => \my $out,
'file=s' => \my $file,
)
or usage();