.\"	$OpenBSD: talk.1,v 1.15 2002/11/14 02:57:28 deraadt Exp $
.\"	$NetBSD: talk.1,v 1.3 1994/12/09 02:14:23 jtc Exp $
.\"
.\" Copyright (c) 1983, 1990, 1993
.\"	The Regents of the University of California.  All rights reserved.
.\"
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.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 3. All advertising materials mentioning features or use of this software
.\"    must display the following acknowledgement:
.\"	This product includes software developed by the University of
.\"	California, Berkeley and its contributors.
.\" 4. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
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.\"
.\"     @(#)talk.1	8.1 (Berkeley) 6/6/93
.\"
.Dd June 6, 1993
.Dt TALK 1
.Os
.Sh NAME
.Nm talk
.Nd talk to another user
.Sh SYNOPSIS
.Nm talk
.Op Fl Hs
.Ar person
.Op Ar ttyname
.Sh DESCRIPTION
.Nm
is a visual communication program which copies lines from your
terminal to that of another user.
.Pp
The command arguments are as follows:
.Bl -tag -width ttyname
.It Fl H
Don't escape characters with the high big set.
This may be useful for certain character sets, but could cause erratic 
behaviour on some terminals.
.It Fl s
Use smooth scrolling in the
.Nm
window.
The default is to clear the next two rows and jump from the bottom of
the window to the top.
.It Ar person
If you wish to talk to someone on your own machine, then
.Ar person
is just the person's login name.
If you wish to talk to a user on another host, then
.Ar person
is of the form
.Ql user@host .
.It Ar ttyname
If you wish to talk to a user who is logged in more than once, the
.Ar ttyname
argument may be used to indicate the appropriate terminal
name, where
.Ar ttyname
is of the form
.Ql ttyXX .
.El
.Pp
When first called,
.Nm
sends the message
.Pp
.Bd -literal -offset indent -compact
Message from Talk_Daemon@localhost...
talk: connection requested by your_name@your_machine.
talk: respond with: talk your_name@your_machine
.Ed
.Pp
to the user you wish to talk to.
At this point, the recipient of the message should reply by typing
.Pp
.Dl $ talk \ your_name@your_machine
.Pp
It doesn't matter from which machine the recipient replies, as
long as the login name is the same.
If the machine is not the one to which
the talk request was sent, it is noted on the screen.
Once communication is established,
the two parties may type simultaneously, with their output appearing
in separate windows.
Typing control-L
.Pq Ql ^L
will cause the screen to
be reprinted, while the erase, kill, and word kill characters will
behave normally.
To exit, just type the interrupt character;
.Nm
then moves the cursor to the bottom of the screen and restores the
terminal to its previous state.
.Pp
Permission to talk may be denied or granted by use of the
.Xr mesg 1
command.
At the outset talking is allowed.
Certain commands, in particular
.Xr nroff 1
and
.Xr pr 1 ,
disallow messages in order to
prevent messy output.
.Sh FILES
.Bl -tag -width /var/run/utmp -compact
.It Pa /etc/hosts
to find the recipient's machine
.It Pa /var/run/utmp
to find the recipient's tty
.El
.Sh SEE ALSO
.Xr mail 1 ,
.Xr mesg 1 ,
.Xr who 1 ,
.Xr write 1
.Sh HISTORY
The
.Nm
command appeared in
.Bx 4.2 .
.Sh BUGS
The version of
.Xr talk 1
released with
.Bx 4.3
uses a protocol that
is incompatible with the protocol used in the version released with
.Bx 4.2 .