Inserting a parameter into a string

The object is I'm making a universal function that do file writing, copy, and moving. I want the function to be able to take the program you want to transfer as a parameter and input that into the string that it write to the file.
For example this is my current code.

function transfer(type)
  fs.copy(type, "disk/"..type.."Prog")
  file = fs.open("disk/startup", "w")
  file.writeLine("fs.move(\"disk/\""..type.."\"Prog\","..type..")")
  file.writeLine("shell.run(\"receive \""..type..")")
  file.close()
end

The Object is that when I were to pass in a program name(lets say "build"). I want it where when it writes to the disk by the end the disk is reading.

fs.move("disk/buildProg", "build")

But when its done it reads.

fs.move("disk/"build"Prog", build)

I understand why it does that looking back and forth. Would I do a string.gsub to replace the text in the string with the one I want to be in there.

Something like

string.gsub("fs.move(\"disk/type/Prog\", \"type\")", "type", type)

I would do some variable changes to make it easier to read.

You're adding the problematic quotes in yourself. Why not just remove them from the statement that writes the string?

Yea. Taking another look at it I see. This is how I changed it.

file.writeLine("fs.move(\"disk/"..type.."Prog\", \""..type.."\")")

I believed I type that right when putting it here.
It gets difficult following along when doing something like that.