[net.sources] nwrite.man

flamer@omsvax.UUCP (08/12/83)

.TH NWRITE 1 intel.local
.SH NAME
nwrite \- new write, talk to n \(>= 2 users
.SH SYNOPSIS
.B nwrite \ 
[
.BI \-e c 
]
.SH DESCRIPTION
.I Nwrite
copies lines from your terminal to those of other users.  This allows
communication similar to a phone call to exist between two or more
users on a 
.SM UNIX 
system.  One user calls another by using the
.B ~c
command, causing a message to be displayed on the callee's terminal if
it was not write protected with
.I mesg
.IR n \.
The recipient of the message should run
.I nwrite
and call back.  Communication continues until all users hang up.
.PP
There is one optional command argument, 
.BI \-e c,
which replaces the command lead-in character from a tilde to
.IR c \.
This is for the poor souls who use Hazeltine terminals where tilde
masquerades for an escape.
.PP
These are the commands in detail:
.PP
.B ~c\ 
.RI [ login_name 
.RI [ tty_name ]]
.RS
Call the user on
.IR login_name \.
If more than one user is logged on to
.IR login_name ,
the
.I tty_name
must be specified.  As each new user calls in with
.BR ~c ,
he becomes part of the conference call.  If a user calls someone not
already in some conversation, a new conversation is created.  This
command sends the message:
.sp 1
.RS
Message from:
.I your_name
on 
.I your_tty_name
at
.IR current_time \...
.RE
.RE
.PP
.B ~e
.RS
Toggle tty echo-plex.  Some terminals (such as at Oregon State
University) are hard-wired as half-duplex, which the Version 7
tty driver doesn't really support.  Using this tilde escape will get 
these terminals to work sensibly.
.RE
.PP
.B ~h
.RS
Hang up.  You are removed from the conversation and returned to
.IR limbo-land \.
You may then call into a new conversation or exit to the shell.
This command sends the message:
.sp 1
.RS
[over and out:
.I your_name
on
.I your_tty_name
at
.IR current_time ]
.RE
.RE
.PP
.B ~o
.RS
Send `over' message.  If more than two people are talking, it is
necessary to differentiate between the callers.  Because of this,
.I nwrite
has a built-in protocol that
.I write
does not have.  When
.B ~o
is typed, all other callers will receive the message:
.sp 1
.RS
[over:
.I your_name 
on 
.I your_tty_name 
at
.IR current_time ]
.RE
.RE
.PP
.B ~q
.RS
Quit
.IR nwrite ,
that is, exit to the shell.  You may type
.B ~q
at any time, even if you have write control, and all of the necessary
`over' and `over and out' messages will be supplied for you.
.RE
.PP
.B ~w
.RS
Print a list, similar to the
.I who
command, that shows what people on which terminals are in which 
conversations.  A person listed as being in conversation
.I `\-'
is in 
.I limbo-land
(that is, not in any conversation).
.RE
.PP
.B !
.RI [ command ]
.RS
Temporarily escape to a shell command.  If it is typed alone, a new
subshell will be created.  To return to
.I nwrite
from the Bourne shell you should type a control-D, and to return from
the C shell with
.B ignoreeof
set, type
.I exit.
.RE
.PP
.B ?
.RS
Print out a summary help list similar to this one.
.RE
.PP
.B control-D
.RS
Hang up.  Same as
.B ~q
but works anywhere on a line, not just at the beginning.
.RE
.PP
.B escape
.RS
Relinquish write control.  Same as
.B ~o
but works anywhere on a line, not just at the beginning.
.RE
.PP
.I text
.RS
If you do not have write control, you cannot talk.  Write control is gained
by typing text.  If the conversation is in such a state that you can get
write control (no one else is typing), the text will be shown and become
part of your message.  If someone else has control, your text will be
ignored.  To prevent against indescriminate terminal hogs, there is a
15 second non-activity time out for people with write control.
.RE
.SH FILES
.ta 2i
/etc/utmp	to find user 
.br
.RI /dev/ ttynn	 to
send message generated by
.B ~c
to callee 
.br
/bin/sh	to execute a
.RB ` ! '
.br
/bin/csh	to execute a
.RB ` ! '
for
.I csh
users 
.br
/bin/mail	to send
.B ~c
message to write protected user 
.br
/tmp/nwrite.master	to keep conversation table (see 
.BR ~w )
.br
.RI /tmp/nwrite.conv nn	 to
provide writer lock control 
.br
.RI /tmp/nwrite. pid	 to
give user of process
.I pid
write control 
.br
.SH SEE ALSO
mail(1), \ mesg(1), \ who(1), \ write(1)
.SH AUTHOR
Jim Trethewey
.SH BUGS
Uses advanced signals not available in standard Version 7.  They can be
removed without too much ill effect.
.PP
Slow on PDP-11's.