(no options) 

Send a message to all connected clients. 

-u username

Send a message to a specific user. 

-c clientname

Send a message to a specific client, whose name you can learn with tninfo -f.

-s service

Send a message to all clients connected to a specific service. 

-n NBclient

Send a message to a specific NetBIOS client. 

message 

Enter the message text to send to clients.