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.\"     from: @(#)talk.1	6.6 (Berkeley) 4/22/91
.\"	$Id: talk.1,v 1.15 2000/07/30 23:57:02 dholland Exp $
.\"
.Dd November 24, 1999
.Dt TALK 1
.Os "Linux NetKit (0.17)"
.Sh NAME
.Nm talk
.Nd talk to another user
.Sh SYNOPSIS
.Nm talk
.Ar person
.Op Ar ttyname
.Sh DESCRIPTION
.Nm Talk
is a visual communication program which copies lines from your
terminal to that of another user.
.Pp
Options available:
.Bl -tag -width ttyname
.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
or
.Ql pts/X .
.El
.Pp
When first called,
.Nm talk
contacts the talk daemon on the other user's machine, which sends the
message
.Bd -literal -offset indent -compact
Message from TalkDaemon@his_machine...
talk: connection requested by your_name@your_machine.
talk: respond with: talk your_name@your_machine
.Ed
.Pp
to that user. At this point, he then replies by typing
.Pp
.Dl talk \ your_name@your_machine
.Pp
It doesn't matter from which machine the recipient replies, as
long as his login name is the same.  Once communication is established,
the two parties may type simultaneously; their output will appear
in separate windows.  Typing control-L (^L)
.\".Ql ^L
will cause the screen to
be reprinted. The erase, kill line, and word erase characters
(normally ^H, ^U, and ^W respectively)
will behave normally.  To exit, just type the interrupt character
(normally ^C);
.Nm talk
then moves the cursor to the bottom of the screen and restores the
terminal to its previous state.
.Pp
As of netkit-ntalk 0.15
.Nm talk
supports scrollback; use esc-p and esc-n to scroll your window, and
ctrl-p and ctrl-n to scroll the other window. These keys are now
opposite from the way they were in 0.16; while this will probably be
confusing at first, the rationale is that the key combinations with 
escape are harder to type and should therefore be used to scroll one's
own screen, since one needs to do that much less often.
.Pp
If you do not want to receive talk requests, you may block them using the
.Xr mesg 1
command.  By default, talk requests are normally not blocked.
Certain commands, in particular
.Xr nroff 1 ,
.Xr pine 1 ,
and
.Xr pr 1 ,
may block messages temporarily in order to
prevent messy output.
.Pp
.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 ,
.Xr talkd 8
.Sh BUGS
The protocol used to communicate with the talk daemon is braindead.
.Pp
Also, the version of
.Xr talk 1
released with
.Bx 4.2
uses a different and even more braindead protocol that is completely
incompatible. Some vendor Unixes (particularly those from Sun) have
been found to use this old protocol. There's a patch from Juan-Mariano de
Goyeneche (jmseyas@dit.upm.es) which makes talk/talkd, if compiled with
-DSUN_HACK, compatible with SunOS/Solaris' ones. It converts messages from
one protocol to the other.
.Pp
Old versions of
.Nm talk
may have trouble running on machines with more than one IP address,
such as machines with dynamic SLIP or PPP connections. This problem is
fixed as of netkit-ntalk 0.11, but may affect people you are trying to
communicate with.
.Sh HISTORY
The
.Nm
command appeared in
.Bx 4.2 .