WALL(1) Linux User's Manual WALL(1)
wall -- send a message to everybody's terminal.
wall [ message ]
Wall sends a message to everybody logged in with their mesg(1) permis-
sion set to yes. The message can be given as an argument to wall, or it
can be sent to wall's standard input. When using the standard input
from a terminal, the message should be terminated with the EOF key
The length of the message is limited to 20 lines.
There is an undocumented (well not anymore..) option, "-n", that
supresses the banner printed by wall . This is for usage by rwalld
(8). Wall will not allow you to use that flag if wall is installed
set-group-id and the user executing wall is not root.
For every invocation of wall a notification will be written to syslog,
with facility LOG_USER and level LOG_INFO.
Wall ignores the TZ variable - the time printed in the banner is based
on the systems local time.
Miquel van Smoorenburg, email@example.com
12 September 2000 WALL(1)