There are lot of great tools available in gnome to send messages over network or a local host computer .
There are 3 Options
1.zenity – It will display a default ok box on the screen
2.notify-send -This will give a Popup box in the system tray
3. xmessage – This will give a box like the first one.
zenity – display GTK+ dialogs
zenity --info --text "message here"
this will give you a standard gtk box
Will give you a calendar – More options are there
this will show a pop up box in the system tray.
notify-send ["title"] "message"
-t will auto expire in milliseconds
notify-send ["title"] "message" -t 500
-u is urgency (low,normal,critical)
in the new versions of gnome this popup box is great.
The third option is xmessage. This will create a message box using the x library.
xmessage – display a message or query in a window (X-based /bin/echo).
The xmessage program displays a window containing a message from the
command line, a file, or standard input. Along the lower edge of the
message is row of buttons; clicking the left mouse button on any of
these buttons will cause xmessage to exit. Which button was pressed is
returned in the exit status and, optionally, by writing the label of
the button to standard output.
Some notable options are
-center – the message at center
-nearmouse – the message near mouse
-timeout secs – will close after some seconds.
You can get more info using
xmessage -center "can we go for a tea ?"
For message over a local or remote network . You want to apply some trick.
After login export the users x settings to that machines DISPLAY variable . For that type
~]$ DISPLAY=:0; XAUTHORITY=~owner_of:0/.Xauthority; export DISPLAY XAUTHORITY
You will probably need to parse the output of `who` for the display and
user name, that way you can send the message to everyone who is logged
in to X on that machine.
Happy messaging and chatting using gnome. (Greate User Interface – with greate utilities).
Happy Hacking ……!!!!