The fingerd utility uses a simple protocol based on RFC1196 that provides an interface to finger(1) at several network sites. It is supposed to return a friendly, human-oriented status report on either the system at the moment or a particular person in depth. There is no required format and the protocol consists mostly of specifying a single ""command line"", thus, fingerd can also be used to implement other protocols in conjunction with the -p flag.
The fingerd utility is started by inetd(8), which listens for TCP requests at port 79. Once connected it reads a single command line terminated by a <CRLF> which is passed to finger(1). The fingerd utility closes its connections as soon as the output is finished.
If the line is null (i.e., just a <CRLF> is sent) then finger(1) returns a "default" report that lists all people logged into the system at that moment.
If a user name is specified (e.g. eric<CRLF>) then the response lists more extended information for only that particular user, whether logged in or not. Allowable "names" in the command line include both "login names" and "user names". If a name is ambiguous, all possible derivations are returned.
The following options may be passed to fingerd as server program arguments in /etc/inetd.conf: