Returns a handle to a temporary file, opened in update mode. Automatically removed when the program ends.
f = io.tmpfile () -- open temporary file
f:write ("some data here") -- write to it
f:seek ("set", 0) -- back to start
s = f:read ("*a") -- read all of it back in
print (s) -- print out
f:close () -- close file
-->
some data here