rwall(1)

NAME
     rwall - write to all users over a network

SYNOPSIS
     rwall host1 host2 ...
     rwall -n netgroup1 netgroup2 ...
     rwall -h host -n netgroup

DESCRIPTION
     Rwall reads a message from standard input until end-of-file.  It then
     sends this message, preceded by the line ``Broadcast Message ...'', to
     all users logged in on the specified host machines.  With the -n option,
     it sends to the specified network groups, which are defined in
     netgroup(4).

     A machine can only receive such a message if it is running rwalld(1m),
     which is normally started up by the daemon inetd(1m).

SEE ALSO
     wall(1), rwalld(1M), netgroup(4)

BUGS
     The timeout is fairly short in order to be able to send to a large group
     of machines (some of which may be down) in a reasonable amount of time.
     Thus the message may not get through to a heavily loaded machine.