WRITE (I)                    3/15/72                    WRITE (I)

NAME            write  --  write to another user

SYNOPSIS        write user

DESCRIPTION     write copies lines from your typewriter to that

                of another user.  When first called, write sends

                the message

                     message from yourname...

                The recipient of the message should write back at

                this point.  Communication continues until an end

                of file is read from the typewriter or an inter-

                rupt is sent.  At that point write writes "EOT"

                on the other terminal.

                Permission to write may be denied or granted by

                use of the mesg command.  At the outset writing

                is allowed.  Certain commands, in particular roff

                and pr, disallow messages in order to prevent

                messy output.

                If the character "!" is found at the beginning of

                a line, write calls the mini-shell msh to execute

                the rest of the line as a command.

                The following protocol is suggested for using

                write: When you first write to another user, wait

                for him to write back before starting to send.

                Each party should end each message with a dis-

                tinctive signal ("(o)" for "over" is conven-

                tional) that the other may reply.  "(oo)" (for

                "over and out") is suggested when conversation is

                about to be terminated.

FILES           /tmp/utmp       to find user

                /etc/msh        to execute !

SEE ALSO        mesg(I), msh(VII)

DIAGNOSTICS     "user not logged in"; "permission denied".

BUGS            write should check the mode of the other user's

                typewriter and refuse to proceed unless non-user

                write permission is given.  Currently it is pos-

                sible to write to another person with the same

                user-ID even though he has forbidden messages.

                write should also allow specification of the

                typewriter name of a user who is logged in sev-

                eral times instead of picking out the instance

                with the lowest name.