Fix a NULL pointer dereference when a DDB 'ps' attempts to

[dragonfly.git] / usr.bin / finger / finger.1

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.\"     @(#)finger.1    8.3 (Berkeley) 5/5/94
.\" $FreeBSD: src/usr.bin/finger/finger.1,v 1.9.2.12 2003/02/25 20:31:18 trhodes Exp $
.\" $DragonFly: src/usr.bin/finger/finger.1,v 1.4 2004/09/03 19:13:23 dillon Exp $
.\"
.Dd August 30, 2004
.Dt FINGER 1
.Os
.Sh NAME
.Nm finger
.Nd user information lookup program
.Sh SYNOPSIS
.Nm
.Op Fl 468glmpshoT
.Op Ar user ...\&
.Op Ar user@host ...\&
.Sh DESCRIPTION
The
.Nm
utility displays information about the system users.
.Pp
Options are:
.Bl -tag -width indent
.It Fl 4
Forces
.Nm
to use IPv4 addresses only.
.It Fl 6
Forces
.Nm
to use IPv6 addresses only.
.It Fl 8
Pass through 8-bit data.  This option is intended for enabling 8-bit
data output in the
.Xr fingerd 8
service.  Using this from the command line is
.Em dangerous ,
as the output data may include control characters for your terminal.
.It Fl s
Display the user's login name, real name, terminal name and write
status (as a ``*'' before the terminal name if write permission is
denied), idle time, login time, and either office location and office
phone number, or the remote host.
If
.Fl o
is given, the office location and office phone number is printed
(the default).
If
.Fl h
is given, the remote host is printed instead.
.Pp
Idle time is in minutes if it is a single integer, hours and minutes
if a ``:'' is present, or days if a ``d'' is present.
If it is an
.Dq * ,
the login time indicates the time of last login.
Login time is displayed as the day name if less than 6 days, else month, day;
hours and minutes, unless more than six months ago, in which case the year
is displayed rather than the hours and minutes.
.Pp
Unknown devices as well as nonexistent idle and login times are
displayed as single asterisks.
.It Fl h
When used in conjunction with the
.Fl s
option, the name of the remote host is displayed instead of the office
location and office phone.
.It Fl o
When used in conjunction with the
.Fl s
option, the office location and office phone information is displayed
instead of the name of the remote host.
.It Fl g
This option restricts the gecos output to only the users' real
name.
It also has the side-effect of restricting the output
of the remote host when used in conjunction with the
.Fl h
option.
.It Fl l
Produce a multi-line format displaying all of the information
described for the
.Fl s
option as well as the user's home directory, home phone number, login
shell, mail status, and the contents of the files
.Pa .forward ,
.Pa .plan ,
.Pa .project
and
.Pa .pubkey
from the user's home directory.
.Pp
If idle time is at least a minute and less than a day, it is
presented in the form ``hh:mm''.
Idle times greater than a day are presented as ``d day[s]hh:mm''.
.Pp
Phone numbers specified as eleven digits are printed as ``+N-NNN-NNN-NNNN''.
Numbers specified as ten or seven digits are printed as the appropriate
subset of that string.
Numbers specified as five digits are printed as ``xN-NNNN''.
Numbers specified as four digits are printed as ``xNNNN''.
.Pp
If write permission is denied to the device, the phrase ``(messages off)''
is appended to the line containing the device name.
One entry per user is displayed with the
.Fl l
option; if a user is logged on multiple times, terminal information
is repeated once per login.
.Pp
Mail status is shown as ``No Mail.'' if there is no mail at all, ``Mail
last read DDD MMM ## HH:MM YYYY (TZ)'' if the person has looked at their
mailbox since new mail arriving, or ``New mail received ...'', ``Unread
since ...'' if they have new mail.
.It Fl p
Prevent
the
.Fl l
option of
.Nm
from displaying the contents of the
.Pa .forward ,
.Pa .plan ,
.Pa .project
and
.Pa .pubkey
files.
.It Fl m
Prevent matching of
.Ar user
names.
.Ar User
is usually a login name; however, matching will also be done on the
users' real names, unless the
.Fl m
option is supplied.
All name matching performed by
.Nm
is case insensitive.
.It Fl T
Disable the piggybacking of data on the initial connection request.
This option is needed to finger hosts with a broken TCP implementation.
.El
.Pp
If no options are specified,
.Nm
defaults to the
.Fl l
style output if operands are provided, otherwise to the
.Fl s
style.
Note that some fields may be missing, in either format, if information
is not available for them.
.Pp
If no arguments are specified,
.Nm
will print an entry for each user currently logged into the system.
.Pp
The
.Nm
utility may be used to look up users on a remote machine.
The format is to specify a
.Ar user
as
.Dq Li user@host ,
or
.Dq Li @host ,
where the default output
format for the former is the
.Fl l
style, and the default output format for the latter is the
.Fl s
style.
The
.Fl l
option is the only option that may be passed to a remote machine.
.Pp
If the file
.Pa .nofinger
exists in the user's home directory,
.Nm
behaves as if the user in question does not exist.
.Pp
The optional
.Xr finger.conf 5
configuration file can be used to specify aliases.
Since
.Nm
is invoked by
.Xr fingerd 8 ,
aliases will work for both local and network queries.
.Sh ENVIRONMENT
The
.Nm
utility utilizes the following environment variable, if it exists:
.Bl -tag -width Fl
.It Ev FINGER
This variable may be set with favored options to
.Nm .
.El
.Sh FILES
.Bl -tag -width /var/log/lastlog -compact
.It Pa /etc/finger.conf
alias definition data base
.It Pa /var/log/lastlog
last login data base
.El
.Sh SEE ALSO
.Xr chpass 1 ,
.Xr w 1 ,
.Xr who 1 ,
.Xr finger.conf 5 ,
.Xr fingerd 8
.Rs
.%A D. Zimmerman
.%T The Finger User Information Protocol
.%R RFC 1288
.%D December, 1991
.Re
.Sh HISTORY
The
.Nm
command appeared in
.Bx 3.0 .
.Sh BUGS
The current FINGER protocol RFC requires that the client keep the connection
fully open until the server closes.
This prevents the use of the optimal
three-packet T/TCP exchange.
(Servers which depend on this requirement are
bogus but have nonetheless been observed in the Internet at large.)