.TH UTALK 1 "Nov 24, 1996" "Roger Espel Llima"
.SH NAME
utalk \- a UDP-based full screen talk program
.SH SYNOPSIS
.PD 0
.B utalk
[options] user[@host][#tty]
.PP
.B utalk
[options] !port@host
.PP
.B utalk
[options] -s port
.PP
.B utalk
[options] -c host port
.PD
.SH OPTIONS
.TP
.BR "-s, --server"
Tells
.B utalk
not to use the talk daemons to announce itself, and instead wait for
a connection on the given port number.
.TP
.BR "-c, --client"
Tells
.B utalk
not to use the talk daemons to announce itself, and instead connect to
the given port number on the given host.
.TP
.BR "-a, --announce-only"
Makes
.B utalk
decide on a local port number, and send out an announce with the port
number instead of your username.  Useful to start a 
.B utalk
session with a host that has a talk daemon when yours doesn't.
.TP
.BR "-7, --seven-bit"
Makes 
.B utalk
convert all characters to 7-bit US-ASCII before displaying them; useful
if you don't have an iso-8859-1 capable terminal.
.TP
.BR "-8, --eight-bit"
Makes
.B utalk
show iso-8859-1 encoded characters on the screen, as they are received.
.SH ARGUMENTS
.TP
.BR "user@host[#tty]"
Specifies the user to ring.  The "user@host" part can be replaced
with an alias name defined in your
.B ~/.utalkrc.
If you specify the tty, 
.B utalk
will ask the talk daemon to ring the user on that particular tty.
The username can be prefixed by a '!', which 
.B utalk
will strip.
.TP 
.BR "!port@host"
Specifies the port number to connect to, and the host.  Useful to answer
to a
.BR "utalk -a" .

.SH DESCRIPTION
.B utalk
is a text-based chat program in the vein of
.B talk 
and 
.BR YTalk ,
which uses a better protocol built over UDP for communication.  Because
it does not require that network packets arrive in sequence to be able
to display them, 
.B utalk
can be used over unreliable links where a TCP/IP connection such as a
telnet or a talk would be too slow to be usable.
.LP
Additionally,
.B utalk
supports full editing of previously typed text, scrollback, keyboard
bindings, and aliases.
.LP
.B utalk
is 
.I incompatible
with any other talk programs, as it uses a completely different protocol.
Unfortunately, the text "respond with:  talk" is hard-coded in the
talk daemon, and cannot be set by the client.
.LP
To avoid confusion, 
.B utalk's
talk requests send the username prefixed with a '!', which must be 
understood as ``respond with 
.BR utalk ''.

.SH DISPLAY
As in
.B talk 
and 
.BR YTalk ,
the 
.B utalk
screen is divided in a number of separate scrolling areas, one for
yourself and one for each other connected client (currently limited to
one).  
.LP
At any time, one of these windows is active.  Each scrolling area
has a status line at the top, with the name of the client and the
following flags:
.TP
.BR "[m]"
This flag is always present on the top window: it's "\fBm\fPy" window.
.TP
.BR "[*]"
This flag means that the window is active and in read-write mode.  This
is the normal mode for your own window;  in this mode, you can type and
edit, and when you move your cursor and/or scroll back all other
connected clients see the cursor move too.
.TP
.BR "[R]"
This flag means that the window is active and in read-only mode.  This is
the only way another window than yours can be active (i.e you can't
type text in someone else's window); setting your own window in read-only
mode lets you scroll back through what you typed without all other clients
seeing your do it.
.TP
.BR "[n]"
Means that the window is not yet connected; the user hasn't responded
yet.
.TP
.BR "[c]"
Means that the window is connected.
.TP
.BR "[b]
Means that the window is connected, but no data (even control data that
.B utalk
sends periodically) has been received for a while, so the connection might
be broken or the client on the other side might have crashed.
.B utalk
will not interrupt a connection because of this, it's up to you to stop it
after a while if it doesn't come back.

.SH EDITING
.BR utalk 's
editing keys can be configured to emulate either 
.B vi
or
.BR emacs ,
in a limited way.  By default,
.B utalk
is in emacs mode.
.LP
.B utalk
keeps a table of bindings for each of three modes: emacs mode,
vi command mode, and vi insert mode.  These tables are initialized
to suitable defaults, and you can add bindings with the
.I bind
command in your ~/.utalkrc file.
.LP
The following is a list of all key commands and their default bindings
in emacs mode, vi command mode, and vi insert mode respectively.

.TP
.BR "self-insert (printable chars) (unbound) (printable chars)"
The keypress gets inserted at the current cursor position, and the
cursor moves forward one step.
.TP
.BR "insert-in-place (unbound) (unbound) (unbound)"
The keypress gets inserted at the current cursor position, and the
cursor does not move.
.TP
.B "quote-char (^Q) (unbound) (^V)"
Insert the following key literally.
.TP
.BR "tab (^I) (unbound) (^I)"
Moves the cursor to the next tab stop.
.TP
.BR "new-line (^M, ^J) (^M, ^J) (^M, ^J)"
Moves the cursor to the first position on the next line, possibly
creating the line.
.TP
.BR "delete (^D) (x) (unbound)"
Deletes the character under the cursor.
.TP
.BR "delete-end-of-line (^K) (D, d$) (unbound)"
Deletes from the cursor to the end of the line.
.TP
.BR "delete-beginning-of-line (unbound) (d0, d^) (unbound)"
Deletes from the beginning of the line to the cursor.
.TP
.BR "delete-line (^U) (dd) (^U)"
Deletes the current line.
.TP
.BR "delete-word (ESC d) (dw, dW) (unbound)"
Deletes to the beginning of the next word.
.TP
.BR "delete-end-of-word (unbound) (de) (unbound)"
Deletes to the end of the current word.
.TP 
.B "backspace (^H, DEL) (X) (^H, DEL)"
Moves back the cursor one position, erasing the character in that position.
.TP
.B "backspace-word (^W) (unbound) (^W)"
Backspaces over one word.
.TP
.B "backward (^B, ESC [D) (h, [D) (unbound)"
Moves backward one position.
.TP
.B "forward (^F, ESC [C) (l, [C) (unbound)"
Moves forward one position.
.TP
.B "backward-word (ESC b) (b, B) (unbound)"
Moves backward one word.
.TP
.B "forward-word (ESC f) (w, W) (unbound)"
Moves forward one word.
.TP
.B "end-of-word (unbound) (e) (unbound)"
Moves to the end of the current word.
.TP
.B "beginning-of-line (^A) (0, ^) (unbound)"
Moves to the beginning of the current line.
.TP
.B "end-of-line (^E) ($) (unbound)"
Moves to the end of the current line.
.TP
.B "nop (unbound) (ESC) (unbound)"
Does nothing.
.TP
.B "beep (unbound) (unbound) (unbound)"
Beeps the terminal (does not send a beep across to the other clients).
.TP
.B "up (^P, ESC [A) (k, [A) (unbound)"
Moves the cursor up one line.
.TP
.B "down (^N, ESC [B) (j, [B) (unbound)"
Moves the cursor down one line.
.TP
.B "up-page (ESC v) (^B) (unbound)"
Moves the cursor up one page if the screen is in read/write mode, and
scrolls up by one page if it is in read-only mode.
.TP
.B "down-page (^V) (^F) (unbound)"
Moves the cursor down one page if the screen is in read/write mode, and
scrolls down by one page if it is in read-only mode.
.TP
.B "up-half-page (unbound) (^U) (unbound)"
Moves the cursor up half a page if the screen is in read/write mode, and
scrolls up by half a page if it is in read-only mode.
.TP
.B "down-half-page (unbound) (^D) (unbound)"
Moves the cursor down half a page if the screen is in read/write mode, and
scrolls down by half a page if it is in read-only mode.
.TP
.B "top-of-screen (unbound) (H) (unbound)"
Moves the cursor to the first line of the current visible screen.
.TP
.B "middle-of-screen (unbound) (M) (unbound)"
Moves the cursor to the middle of the screen.
.TP
.B "bottom-of-screen (unbound) (L) (unbound)"
Moves the cursor to the last line of the current visible screen.
.TP
.B "top-or-up-page (unbound) (unbound) (unbound)"
Moves the cursor to the top of the screen if it's not there, or scrolls
up by one page if it is.
.TP
.B "bottom-or-down-page (unbound) (unbound) (unbound)"
Moves the cursor to the bottom of the screen if it's not there, or
scrolls down by one page if it is.
.TP
.B "vi-goto-line (unbound) (G) (unbound)"
Moves the cursor to the line number entered as a prefix, if any; otherwise
moves to the last line of the buffer.
.TP
.B "redisplay (^L) (^L) (^L)"
Redraws the screen.
.TP
.B "resynch (^R) (^R) (^R)"
Requests immediate transmission of all missing packets.
.TP
.B "next-window (^X b, ^X o, ^G) (g) (unbound)"
Cycles the active window between your window in read/write mode, your
window in read-only mode, and each of the other windows.
.TP
.B "set-topic (^T) (^T) (unbound)
Prompts the user for a ``topic'', which will be displayed at the top of
the screen for all users.
.TP
.B "vi-insert-mode (unbound) (i, R) (unbound)"
Sets vi insert mode.
.TP
.B "vi-command-mode (unbound) (unbound) (unbound)"
Sets vi command mode.
.TP
.B "emacs-mode (unbound) (unbound) (unbound)"
Sets emacs mode.
.TP
.B "quit (^X c) (ZZ) (unbound)"
Quits
.BR utalk .
.TP
.B "vi-escape (unbound) (unbound) (ESC)"
Sets vi command mode and moves the cursor one position to the left.
.TP
.B "vi-add (unbound) (a) (unbound)"
Moves the cursor one position to the right and sets vi insert mode.
.TP
.B "vi-add-at-end-of-line (unbound) (A) (unbound)"
Moves the cursor to the end of the current line and sets vi insert mode.
.TP
.B "vi-insert-at-beginning-of-line (unbound) (I) (unbound)"
Moves the cursor to the beginning of the current line and sets vi insert
mode.
.TP
.B "vi-open (unbound) (o) (unbound)"
Moves the cursor to the beginning of the next line and sets vi insert mode.
.TP
.B "vi-open-above (unbound) (O) (unbound)"
Moves the cursor to the beginning of the previous line and sets vi insert
mode.
.TP
.B "vi-replace-char (unbound) (r) (unbound)"
Replaces the char under the cursor with the following key.
.TP
.B "vi-find-char (unbound) (f) (unbound)"
Moves the cursor to the next occurrence of the following key on the same line.
.TP
.B "vi-reverse-find-char (unbound) (F) (unbound)"
Moves the cursor to the previous occurrence of the following key on the
same line.
.TP
.B "vi-till-char (unbound) (t) (unbound)"
Moves the cursor to one position before the next occurrence of the
following key on the same line.
.TP
.B "vi-reverse-till-char (unbound) (T) (unbound)"
Moves the cursor to one position after the previous occurrence of the
following key on the same line.
.TP
.B "vi-repeat-find (unbound) (;) (unbound)"
Repeats the previous find or till command.
.TP
.B "vi-reverse-repeat-find (unbound) (,) (unbound)"
Repeats the previous find or till command, reversing the direction.
.TP
.B "vi-delete-find-char (unbound) (df) (unbound)"
Deletes all characters between the current position and the next occurrence
of the following key on the same line, both included.
.TP
.B "vi-delete-reverse-find-char (unbound) (dF) (unbound)"
Deletes all characters between the current position and the previous
occurrence of the following key on the same line, both included.
.TP
.B "vi-delete-till-char (unbound) (dt) (unbound)"
Deletes all characters between the current position and the next occurrence
of the following key on the same line, not including the latter.
.TP
.B "vi-delete-reverse-till-char (unbound) (dF) (unbound)"
Deletes all characters between the current position and the previous
occurrence of the following key on the same line, not including the
latter.
.TP
.B "vi-flip-case (unbound) (~) (unbound)"
Flip the case of the character under the cursor.

.SH CONFIGURATION
You can specify a number of settings for
.B utalk
in a configuration file called
.I .utalkrc
in your home directory.
.LP
Valid commands are:
.PP
.RS 4
.PD 0
emacs-mode
.PP
vi-mode
.PP
bind \fIkey\fR \fIfunction\fR
.PP
bind! \fIkey\fR \fIfunction\fR
.PP
alias \fIalias\fR \fIvalue\fR
.PP
set \fIsetting\fR on|off
.RE
.PD 1
.PP
Settings are:
.TP
.B "beep"
Makes utalk let beeps through or silence them.
.TP
.B "word-wrap, wordwrap, ww"
Turns word-wrap on or off (only at the end of the last line in the buffer).
.TP
.B "eight-bit, eightbit, eb"
Lets eight-bit iso-latin-1 characters through or maps them to US-ASCII.
.TP
.B "meta-esc, metaesc, me"
Maps keys with the high bit set to ESC followed by key, or lets them through
(only affects emacs-mode).
.PD
.PP
"toggle" and "se" are synonyms for "set".
.PD 0
.PP
"bindkey" and "bindkey!" are synonyms for "bind" and "bind!", respectively.
.PD 1
.LP
In settings, "on" and "off" arguments are optional, "on" is assumed by
default, unless the setting's name is prefixed with "no".
.PP
Bindings apply to the current mode; to change bindings in vi mode, put a
"vi-mode" first, then your "bind"s and "bind!"s.  In emacs mode, "bind"
and "bind!" are synonymous.
.LP
In a binding, the \fIkey\fR must be a character or sequence of
characters, not separated with any spaces.  The following sequences
are recognized to specify characters:
.PP
.RS 4
.PD 0
^\fIchar\fR, C-\fIchar\fR     --   Control-\fIchar\fR
.LP
M-\fIchar\fR            --   Meta-\fIchar\fR
.LP
\\e                --   ESC
.LP
\\t                --   Tab
.LP
\\r                --   Carriage return (^M)
.LP
\\n                --   Newline (^J)
.LP
\\x\fIhex code\fR        --   Ascii code given in hex
.LP
\\\fIchar\fR             --   That char, taken literally
.RE
.PD 1
.PP
Note that you shouldn't bind functions to M-key combinations in emacs
mode; use ESC key combinations instead, and turn meta-esc on if you want
to use your Meta key like in emacs.
.PD 2
.LP
.PD
You can make aliases for addresses of people to ring, in either of 3 forms:
.TP 12
.B "alias \fIaliasname\fR@ \fIusername\fR@"
Replaces \fIaliasname\fR@\fIhost\fR with \fIusername\fR@\fIhost\fR for
every host. The '@' at the end of \fIusername@\fR is not required.
.TP 12
.B "alias @\fIaliashost\fR @\fIrealhost\fR"
Replaces \fIuser\fR@\fIaliashost\fR with \fIuser\fR@\fIrealhost\fR for
every user. The '@' at the beginning of @\fIrealhost\fR is not required.
.TP 12
.B "alias \fIaliasname\fR \fIuser\fR@\fIhost\fR"
Replaces \fIaliasname\fR with \fIuser\fR@\fIhost\fR.

.SH COPYING
.B utalk
is free software. You can redistribute it and/or modify it under the GNU
General Public License as published by the Free Software Foundation.  See
the file LICENSE for details.

.SH SEE ALSO
.BR talk (1),
.BR ytalk (1),
.BR mesg (1)

.SH FILES
~/.utalkrc           configuration file

.SH BUGS
This is a beta version of 
.BR utalk ,
so some bugs are to be expected...  please report any bugs to the
author.

There is no way to insert (rather than overwrite) text.  This will be
hard to fix, as it is a requirement of 
.B utalk
and the
.B SRDP
protocol that the whole protocol must be commutative.
.LP
There is no way (as of yet...) to do n-way 
.B utalk
sessions.
.LP
The vi and emacs emulations are relatively primitive.

.SH AUTHOR
.B utalk
was written by Roger Espel Llima <roger.espel.llima@pobox.com>.