G'day Fabrizio,

Welcome to the monastery.

Here's a couple of points unrelated to your "pattern matching" query.

I see you've attempted to use lexical variables (with my) throughout your code — which is good. Had you used this line at the top of your code:

use strict;
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The 'vars' stricture of strict would have alerted you to the fact that you'd forgotten to do this for @hostname_short.

Had you also used this line at the top of your code:

use warnings;
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The 'syntax' category of warnings would have emitted a message that actually gave you a better way to write @hostname_short[0]:

Scalar value @hostname_short[0] better written as $hostname_short[0]
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Using both of these pragmata in all of your scripts is a very good idea.

As it turns out, you could have written both of these lines:

@hostname_short = split(/\./,$fqdn,2);

my $hostname = "@hostname_short[0]";
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as just this single line:

my $hostname = (split /\./, $fqdn, 2)[0];
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