command: wall
usage: write a message to every users logged in with their
mesg permission set to yes
syntax: wall [options] [<file>]
examples:
1. To display messages to users from root
# echo server going to down go for break ! | wall
2. To print messages without banner (for only root)
# echo server going to reboot ! | wall -n
3. To print help info of this command
$ wall -h
regards,
dhanasekar
