Reading Don't Use Regular Expressions To Parse IP Addresses! first:

1) Convert the dotted-quad forms to integers.
2) Select the appropriate netmask.
3) Logical AND with the netmask to generate a subnet.
4) Exclusive -or two subnets to compare them.

If you think of the subnets as bitmasks, comparing them with host addresses is trivial.

s//----->\t/;$~="JAPH";s//\r<$~~/;{s|~$~-|-~$~|||s |-$~~|$~~-|||s,<$~~,<~$~,,s,~$~>,$~~>,, $|=1,select$,,$,,$,,1e-1;print;redo}

In reply to Re: IP Address/Subnet matching by starbolin
in thread IP Address/Subnet matching by adenardo

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