write(C)                        19 June 1992                        write(C)


 Name

    write - write to another user

 Syntax

    write user [ tty ]

 Description

    The write command copies lines from your terminal to that of another
    user.  When first called, it sends the message:

          Message from your-logname your-tty ...

    The recipient of the message should write back at this point.  Communica-
    tion continues until an end-of-file is read from the terminal or an
    interrupt is sent.  At that point, write displays:

          (end of message)

    on the other terminal and exits.

    If you want to write to a user who is logged in more than once, the tty
    argument may be used to indicate the appropriate terminal.

    Permission to receive messages from other users of the system may be
    granted or denied by use of the mesg(C) command. By default, users are
    not allowed to receive messages (this is for security).  This may be
    altered by issuing the mesg command from the .login script.

    If the character ``!'' is found at the beginning of a line, write calls
    the shell to execute the rest of the line as a command.  Output from the
    command is sent to the terminal; it is not sent to the remote user.

    The following protocol is suggested for using write:  when you first
    write to another user, wait for him or her to write back before starting
    to send.  Each party should end each message with a distinctive signal
    ((o) for ``over'' is conventional), indicating that the other may reply;
    (oo) for ``over and out'' is suggested when conversation is to be ter-
    minated.

 Files

    /etc/utmp       To find user
    /bin/sh         To execute ``!''

 See also

    hello(C), mail(C), mesg(C), who(C)

 Standards conformance

    write is conformant with:

    AT&T SVID Issue 2;
    and X/Open Portability Guide, Issue 3, 1989.