in reply to bitwise operators

Not your original question, but you might check out Net::Netmask which handles this stuff (including "is this IP in this mask?").

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Re^2: bitwise operators
by Anonymous Monk on Jan 19, 2005 at 21:11 UTC 
    use Socket;

$net = "192.168.0.0";
$mask = "255.255.255.240";
$ip = "192.168.0.5";

print "$ip belongs to $net/$mask\n" if ((net2long($ip) & net2long($mas
+k)) == net2long($net));

sub net2long {

  return unpack("N", inet_aton(shift));

}

    [download]

    2005-01-20 Janitored by Arunbear - added code tags, as per Monastery guidelines

[reply]
[d/l]
      And for CIDR notation use this : 
      use Socket; 

$net = "192.168.0.0"; 
$mask = "28"; # /28 is 255.255.255.240
$ip = "192.168.0.5"; 

print "$ip belongs to $net/$mask\n" if ((net2long($ip) & ~((1 << (32 -
+ $mask)) - 1 )) == net2long($net)); 


sub net2long { return unpack("N", inet_aton(shift)); }

      [download]

      2005-01-20 Janitored by Arunbear - added code tags, as per Monastery guidelines

[reply]
[d/l]

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