1 grepcidr can be used to filter a list of IP addresses against one
2 or more Classless Inter-Domain Routing (CIDR) specifications, or
3 arbitrary networks specified by an address range. As with grep,
4 there are options to invert matching and load patterns from a file.
5 grepcidr is capable of comparing thousands or even millions of IPs
6 to networks with little memory usage and in reasonable computation
9 grepcidr has endless uses in network software, including: mail
10 filtering and processing, network security, log analysis, and many