rednet send

I know I can send a rednet message using rednet.send(ID, "MSG", true) in a program
but how do I make it when using that program to require a variable for the message?

Cause wrote a program for mining turtle for a cobble gen(Seeing how red power isnt out yet)
So I want to tell it how many stacks to gather. Which is all setup, just need to send the turtles a msg with the number of stacks.

You don't need the true argument for rednet.send()

Here's an example to use a var

print("Enter Message")
local msg = read()

rednet.send(ID, msg)