cidrnetmask Function
cidrnetmask converts an IPv4 address prefix given in CIDR notation into
a subnet mask address.
prefix must be given in IPv4 CIDR notation, as defined in
RFC 4632 section 3.1.
The result is a subnet address formatted in the conventional dotted-decimal IPv4 address syntax, as expected by some software.
CIDR notation is the only valid notation for IPv6 addresses, so cidrnetmask
produces an error if given an IPv6 address.
Examples