WRITE(1) WRITE(1)
NAME
write, mesg - write to other users, allow or forbid messages
SYNOPSIS
write person ...
mesg [ n ] [ y ]
DESCRIPTION
Write copies lines from your terminal to terminals of other
persons designated either by login name or (to circumvent
occasional ambiguities) by terminal name as given by who(1).
It announces to each person your login name, your terminal,
and the other persons. To respond, each recipient should
execute a corresponding write to the persons he wants to
talk to.
When you are writing to more than one person, your messages
are identified to the recipients. Writing ceases upon end
of file or interrupt, and the message EOF is sent to the
others.
Write recognizes certain commands during a conversation:
!cmd Execute a shell on the string cmd and then return to
write.
:a person
Add person to the list of people to whom you are talk-
ing, and send an appropriate announcement to all par-
ties. They must do :a for themselves if they want to
include the new person.
:d person
Drop person from your list and make appropriate
announcements.
:l Print a list of people to whom you are talking.
The following protocol is suggested for using write. When
you invoke write, wait for the other user to write back
before starting to send. Each party should end each message
with a distinctive signal that the other may reply - the
customary convention is `(o)' for `over'; (oo) for `over and
out' is suggested when conversation is about to be termi-
nated.
Mesg with argument n forbids messages via write(1) by revok-
ing non-user write permission on the user's terminal. Mesg
with argument y reinstates permission. All by itself, mesg
WRITE(1) WRITE(1)
reports the current state without changing it.
Certain commands, in particular nroff and pr(1) disallow
messages in order to prevent messy output.
FILES
to find user
to execute `!'
SEE ALSO
who(1), mail(1), vismon(9.1)
DIAGNOSTICS
Mesg yields exit status 0 if messages are receivable, 1 if
not, 2 on error.
BUGS
Mux(9.1) generally prevents the receipt of write messages,
but vismon(9.1) permits them.
Messages ought to be identified when the recipient is
receiving from more than one writer, rather than when a
writer is sending to more than one recipient, but that
requires cooperating processes and isn't worth the effort.