Finger HowDoI
finger.howdoi
----------------------------------------------------------------------
jim cerny, jim.cerny@unh.edu
computing and information services
(applies to all our central computing systems)
rev. 12-MAY-1994
...............................................................
Finger is a long-time Unix facility, also defined as an
Internet protocol [1], that lets you obtain information
about users on a system. Finger is not designed as a
comprehensive directory service but it is often useful for
confirming e-mail addresses.
The Finger facility is currently available on all the
central computer systems, both Unix and VAX/VMS [2]. The
basic purpose and use of the Finger command is
straight-forward, but there are various special situations
or 'gotchas' to be aware of. In other words, the
information it searches on and returns to you may vary from
system to system -- not all implemenations have the same
features and options.
Finger searching may be case-sensitive, depending on the
system where the information lives.
In this discussion we use the fictional "Adenoid Filibuster
Smith" who is assumed to have a Unix account of "afs99" and
a VAX/VMS account of "af_smith".
Fingering individuals on your local (logged in) system.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
One reason to finger someone on the system to which you are
loggin in, is to confirm the given name that corresponds to
an account name. On Unix systems if you:
% finger afs99
This matches anyone with the character string 'afs99' as
their account name *or* first or last name as it appears in
the system accounting information.
On VAX/VMS systems (with MULTINET) if you:
$ finger af_smith
This matches anyone with the character string 'af_smith' as
their account name but it does *not* try to match any
portion of the first name or last name as it appears in the
system accounting information.
Another reason to search is when you know the given name but
not the account name. On systems where Finger searches the
given names as well as accounts in the system information
(e.g., this works on Unix systems but not on VAX/VMS
systems), you can:
% finger smith
And this matches anyone with the character string 'smith' as
their account name or as their given first or last name. If
you are uncertain of the spelling of the last name you may
need to be creative in your search, perhaps trying
alternatives such as 'smithe' or 'smythe' since it does not
do any fuzzy pattern-matching.
Since most Finger implementations also report the last time
a person logged in, you can use it to gauge whether they may
have read recent e-mail that you sent to them.
Fingering individuals on other systems.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
To finger someone on another system, specify the Internet
address of that system in addition to the user name that you
are searching for:
finger smith@christa.unh.edu
The information that is returned depends on the
implementation of Finger on the system you are querying, not
on the system you are querying from. And not all systems
support Finger. Either it may not be available for the
particular system or it may be deliberately turned off as a
security or privacy measure [3].
Fingering other systems.
~~~~~~~~~~~~~~~~~~~~~~~~
If you just finger the address of a system, without
reference to a particular account or user name, then Finger
reports on everyone who is *currently* logged in:
finger @christa.unh.edu
Note use of the at-sign to precede the system address. It
may even show you the address of the terminal server or
workstation from which they logged in and how long they have
been connected!
Fingering individuals with a registered alias at UNH.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
We encourage everyone on systems in our 'unh.edu' domain to
register an offical alias with the Alias Manager service
maintained by Computing and Information Services [4]. This
does two important things:
(1) It allows individuals to create one official address to
give to their correspondents, with all e-mail sent to that
address automatically forwarded to an actual local
address. That buffers everyone from the need to
make lots of changes if the actual local address changes.
(2) The database of registered aliases may be searched with
the Finger command to look up someone's e-mail address.
This is particuarly useful if you know they are at UNH
but don't know their e-mail address or perhaps which system
they are on. And the alias database supports searching on
more fields of information than a typical Finger
implementation does.
All registered aliases are attributed to our domain
'@unh.edu' rather than to a specific system. So, to Finger
the registered alias database for the character string of
'smith':
finger smith@unh.edu
This will show anyone with 'smith' as part of either the
alias, or accounts to which the alias points, or description
information (real name plus other information someone
optionally adds).
Fingering complex names.
~~~~~~~~~~~~~~~~~~~~~~~~
Suppose Adenoid Smith's full name were spelled with either a
space or with an non alphanumeric character, such as:
Adenoid Filibuster Le Smith
Adenoid Filibuster-Smith
Then it would be necessary to put the name in quotes:
finger "le smith@christa.unh.edu"
Fingering returns non-name or account information.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Some sites turn off fingering or limit it in various ways as
a security measure, reasoning that it makes it harder for
crackers to get information to attempt break-ins to
accounts. In such cases a Finger command would report:
Connection refused
Some sites also alter their Finger command to return special
information. For example, if you Finger a staff member at
the NEARNET Network Information Center, you will get a
complete roster of staff names and phone numbers, but not
the usual Finger information about the individual:
finger rugo@nic.near.net
Some people make very creative use of the Finger command's
ability to fetch and display a Plan file (described below).
Sometimes a special address is created just to serve up
information that way. A well-known Internet example is the
earthquake information server at the University of
Washington:
finger quake@geophys.washington.edu
Fingering from within a mail program.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Once you become comfortable with basic e-mail use on a
system, you should learn how to use Finger from within the
mail program to look up information. This is very useful if
you go to compose a message to someone and you are uncertain
of their local address.
With VAX/VMS MAIL this is done by issuing a 'spawn' command
from within MAIL (if you are in a captive process, such as
CUFS, you will not be able to spawn):
MAIL> spawn
This suspends your main process and puts you at the system
prompt in a subprocess. At that point you can issue a
Finger command. When ready to resume the main MAIL process
you logout of the subprocess:
$ logout
To suspend your Pine mail process on a Unix system, you need
to plan ahead to enable that capability in Pine. That is,
you need to invoke Pine with the '-z' option. To make this
your default, edit your '.login' file with the Pico editor
to include this line:
alias pine 'pine -z'
What this does, is to let you suspend your Pine process by
typing CTRL-Z. Then you can issue a Finger command. To
resume the Pine process you put it back in the foreground:
% fg
Plan files.
~~~~~~~~~~~
Most Finger implementations allow you to create an optional
"Plan" file. The Plan file is just a file in which you can
place any information that you want displayed in addition to
the usual information that is reported by Finger.
Information commonly included is: mailing address, phone
number, FAX number. And sometimes people include quotations
or graphics that they find amusing.
On Unix systems this is a plain text file called '.plan'
that you create in your home directory with any text editor.
This information is not shown unless you include the host
name as part of the Finger command [5]. That is, this would
*not* show a .plan file on Christa:
% finger afs99
But this would:
% finger afs99@christa.unh.edu
On VAX/VMS systems if the Finger command includes support
for a Plan file then the file is a plain text file in your
home directory called "plan.txt" that must be protected as
world readable:
$ set protection=w:r plan.txt
Unix systems also support a Project file that is similar in
behavior to a Plan file except it is named '.project'.
If don't want to see someone's Plan or Project files when
you Finger them, on Unix systems you can invoke Finger with
two extra flags:
% finger -hp afs99
Wizard stuff.
~~~~~~~~~~~~~
Another way to search for information about someone's
account name or given name on a Unix system is to search for
the particular character string in the password file -- in
the yellow pages password file if it is one of our central
Unix systems:
% ypcat passwd | grep -i afs99
Notes.
~~~~~~
[1] The Finger Internet protocol is specified in RFC1288.
There is a good explanation of Finger in Ed Krol,
"The Whole Internet User's Guide and Catalog," 2nd ed.,
pp. 212-215 (O'Reilly, ISBN:1-56592-063-5, $24.95).
[2] The Finger command is in the process of some change on
the administrative/MIS VAX/VMS systems. At one time it
was necessary to SETUP FINGER and that version of FINGER
will eventually be removed.
[3] The more security and privacy conscious a site is, the
more likely that Finger will not be available.
[4] On our central Unix systems look at:
/usr/local/notes/email_aliases
On our central VAX/VMS systems look at:
doc:email_aliases.txt
[5] Or, unless someone makes their directory and the Plan
file world-readable.