Distributed finger -- finger-like utility designed to share data among several machines
Distributed finger is a utility designed to share info about logged users among several machines connected via network. It has server part and client part (though both run via the same command).
Server part logs information about all user login sessions while client part feeds the server with information about sessions on specific machine.
Server part can then provide clients with information about those sessions, including queries concerning specific user or specific host machine. Those information are provided via protocol heavily based on finger protocol (RFC 1288).
As stated above, the information protocol which server uses to provide information about current and past login sessions is heavily based on finger protocol (RFC 1288). However please keep in mind that this implementation is NOT compliant with finger protocol, not even conditionally.
The most notable difference is handling of {Q2} queries, that is queries with hostname specified. If just one at-sign (@) is found in query, the query is understood as query about logins (either of all users or user specified before that sign) and is served by the server itself, without forwarding the query to specified host.
Dfinger program doesn't accept much options, it's mostly configured by editing configuration file. The only supported option is name of configuration file which should be used.
Dfinger may return one of several error codes if it encounters problems.
- 0 No problem, dfinger exited normally.
- EINVAL Generic error code
- ENOMEM Could not allocate memory
- config Default name of configuration file
There are no known bugs yet which probably means the program still hasn't been tested extensively enough.
Bug submissions are welcome at e-mail karry@karryanna.cz
Say there should be server running at host snowwhite, accessible at 10.10.10.1, and clients running at grumpy and dopey.
The minimal config file for snowwhite is then just IS_SERVER 1 while minimal config file for any of the clients is IS_CLIENT 1 SERVER_ADDR 10.10.10.1
Now just run ./dfinger or eventually ./dfinger /path/to/config on each machine
and clients will start feeding the server with data.
Currently the easist way to retrieve info is probably using telnet though there could be dedicated client one day (or you may of course use common finger client if your server accepts finger requests at standard finger port 79).
So you can for example do telnet localhost 8558 to see karry grumpy pts/7 2m46s 26s :0 karry dopey pts/0 2m29s 2s :0 queen dopey pts/1 8m01s 5m42s me.queen.com.
or telnet localhost 8558 karry@dopey to see only karry dopey pts/0 2m29s 2s :0
Written by Karryanna karry@karryanna.cz, based on idea of Martin Mareš mj@ucw.cz.