I believe your code does what you want. Using the following code:
use strict;
use warnings;
use Getopt::Long;
use Data::Dumper;

my %options;
GetOptions(
    \%options,
    'length|height=i',
);

print Dumper \%options;

[download]
I get the following:
E:\>go.pl --height=1
$VAR1 = {
          'length' => 1
        };

E:\>go.pl --length=1
$VAR1 = {
          'length' => 1
        };

[download]

-enlil

In reply to Re: Another Getopt::Long questions by Enlil
in thread Another Getopt::Long questions by dragonchild

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