Isn't it just the same as using the ServerCmd? Using the same variables and stuff.
Example,
function ServerCmdTest(%client , %a , %b , %c)
{
announce("The user " @ %client @ " has announced \"test\"! " @ %a SPC %b SPC %c);
}
upon messagesending /test star fish star fish star fish it'll announce The user Darren has announced star fish star fish star fish
function ClientCmdTest(%a , %b , %c)
{
echo("The server has sent a message to the client saying " @ %a SPC %b SPC %c);
}
upon the server sending commandToClient(%client , 'test' , "star fish" , "star fish" , "star fish"); it'll echo to the client "star fish star fish star fish"
i am not sure what you are trying to find out, i td;lr'd it because i cba to read today