talk.1

<B>Digital的Unix操作系统VAX 4.2源码</B>

.\" SCCSID: @(#)talk.1	8.1	9/11/90
.TH talk 1
.SH Name
talk, otalk \- talk to another user
.SH Syntax
.B talk
\fIperson\fR [\|\fIttyname\fR\|]
.PP
.B otalk
\fIperson\fR [\|\fIttyname\fR\|]
.SH Description
.NXR "talk program"
.NXR "otalk program"
.NXA "talk program" "write command"
.NXA "mesg command" "talk program"
.NXR "message" "interactive"
The
.PN talk
command is a visual communication program which
copies lines from your terminal to that of
another user.
.PP 
If you wish to talk to someone on your own machine, then
.I person
is just the person's login name. If you wish to talk to
a user on another host, then
.I person
is of the form :
.EX
host!user
 or
host.user
 or
host:user
 or
user@host
.EE
The form
user@host 
is perhaps preferred.
.PP
If you want to talk to a user who is logged in more than once,
the
.I ttyname
argument may be used to indicate the
appropriate terminal name.
.PP
When first called,
it sends the message
.EX
Message from TalkDaemon@his_machine...
talk: connection requested by your_name@your_machine.
talk: respond with: talk your_name@your_machine
.EE
.PP
to the user you wish to talk to. At this point, the recipient
of the message should reply by 
typing 
.EX
talk \ your_name@your_machine
.EE
.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, with their output appearing in separate windows. 
Typing Ctrl-L will cause the screen to be reprinted, while your 
erase, kill, and word kill characters will work in talk as normal.
To exit,
just type your interrupt character;
.PN talk
then moves the cursor to the bottom of the screen and restores 
the terminal.
.PP
Permission to talk may be denied or granted by use of the
.I mesg
command.
At the outset talking is allowed.
Certain commands, in particular
.PN nroff
and 
.MS pr 1
disallow messages in order to prevent messy output.
.PP
In order to use the
.PN talk
program with machines on your network that
may be running earlier versions of ULTRIX, you must initiate
a session with the command
.PN otalk
(/usr/ucb/otalk) instead of the command
.PN talk .
You must also respond to a request from a machine running an older
version of the
.PN talk
program with the
.PN otalk
command. See the Restrictions section.
.SH Examples
The following example demonstrates how to use the
.PN otalk
command.  In this case, user1, whose system (system1) is running
ULTRIX V2.2 initiates a session with 
user2, whose system (system2)
is running ULTRIX V3.0.  User1 types the following:
.EX
system1> talk user2@system2
.EE
The following message appears on the screen of user2:
.EX
Message from Talk_Daemon@system2 at 12:37 ...
talk: connection requested by user1@system1.
talk: respond with:  otalk user1@system1
.EE
To establish the connection user2 follows the instructions
from the Talk_Daemon and types the following at the system
prompt:
.EX
system2> otalk user1@system1
.EE
.SH Restrictions
The version of
.PN talk
released with ULTRIX V3.0 uses a protocol that is incompatible with the
protocol used in earlier versions. Starting with ULTRIX V3.0, the
.PN talk
program
communicates with other machines running ULTRIX, V3.0 (and later), 
and machines running 4.3 BSD or versions of UNIX based on 4.3 BSD.
.PP
The
.PN talk
command is not 8-bit clean. Typing in DEC
Multinational Characters (DECMCS) causes the characters
to echo as a sequence of a carets (^) followed by the
character represented with its high bit cleared. This limitation makes
.PN talk
unusable if
you want to communicate using a language which has DECMCS characters
in its alphabet.
.SH Files
.TP 15
.PN /etc/hosts
to find the recipient's machine
.TP 15
.PN /etc/utmp
to find the recipient's tty
.SH See Also
mail(1), mesg(1), who(1), write(1), talkd(8c)