just a quic hack how subnets can be translated without using a module
my $cidr = 8;
my $mask = "1" x ( 32 - $cidr ) . "0" x $cidr;
print $mask, "\n";
$mask = join ".", ( unpack "C4", ( pack "B*", $mask ) );
print $mask, "\n"

[download]

i also suggest Net::Subnets for working with subnets if it does what you want, in particular matching ip's against subnets is very fast.

In reply to Re^2: behavior of bitwise shift by Taulmarill
in thread behavior of bitwise shift by ngiordano

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