write -- Command

Converse with another user
write user [ tty ]

The  COHERENT  system   provides  several  commands  that  allow  users  to
communicate with  each other.  write allows two logged-in  users to have an
extended, interactive conversation.

write initiates a conversation with user.  If tty is given, write looks for
the user  on that  terminal; this is  useful if a  user is marked  as being
logged in on more than one device.  Otherwise, write holds the conversation
with the first instance of user found on any tty.

If found,  write notifies user  that you are beginning  a conversation with
him.  All  subsequent lines  typed into write  are forwarded to  the user's
terminal, except lines beginning with `!',  which are sent to the shell sh.
Typing end of file (usually <ctrl-D>) terminates write and sends user
the message ``EOT'' to tell him that communication has ended.

Two users  typing lines to write  at about the same  time can cause extreme
confusion,  so users  should agree  on  a protocol  to limit  when each  is
typing.  The  following protocol is suggested.  One  user initiates a write
to another,  and waits until the other user  replies before beginning.  The
first user then types until he  wishes a reply and suffixes ``o'' (over) to
indicate he is through.  The other user does the same, and the conversation
alternates until  one user wishes to terminate it.   This user types ``oo''
(over and out).  The other user  replies in the same way, indicating he too
is finished.   Finally each of the users leave  write by typing end-of-file
(usually <ctrl-D>).

Any user may  deny others the permission to write  to his terminal by using
the command mesg.

Files

/etc/utmp
/dev/*

See Also

commands,
mail,
mesg,
msg,
sh,
wall,
who

Notes

You  should use  write only  for extended conversations.   Use msg  to send
brief communications  to a logged in  user, and mail to  communicate with a
user who  is not  logged in.   wall broadcasts a  message to all  logged in
users.

© 2012 by Stephen A. Ness