The networks file contains information about the known networks that comprise the DARPA (Defense Advanced Research Projects Agency) Internet. Each network is represented by a single line in the networks file. The format for the entries in the networks file is as follows: Name Number Aliases
The fields contain the following: The official network name. The network number. The unofficial names used for the network.
Items on a line are separated by one or more spaces or tab characters. Comments begin with a # (number sign). Routines that search the networks file do not interpret characters from the beginning of a comment to the end of that line. Network numbers are specified in dotted-decimal notation. A network name can contain any printable character except a field delimiter, newline character, or comment character (#).
The networks file is normally created from the official network database maintained at the Network Information Center (NIC). The file may need to be modified locally to include unofficial aliases or unknown networks.
Functions: getnetbyaddr(3), getnetbyname(3), getnetent(3) delim off