JP> The problem is that I am unable to make this work. In simple terms:

 JP>   1. User enters digits until (Enter) key is pressed.
 JP>   2. If letter or punctuation, ignore, supress, wait for another digit.
 JP>   3. If digit, echo to screen and store in a variable.
 JP>   4. When (Enter) pressed, perform calculation on integer variable.

Grab the latest C_ECHO snippets. It has a reasonable line input function
which should be ok as a starting point. No doubt you'll find some of the
other code in there of use as well.

--- MaltEd/2 1.0.b6