unit eco_lib;
   STANDARD constants
   STRING constants
   DOS constants
   CHAR constants
   SCREEN constants
   TYPES used in the unit
   VARIABLES used

   BASE STRING functions
   SECONDARY STRING functions
   PRIMARY DATA CONVERSION functions
   IMPORTANT DOS functions
   DATE functions
   TIMER functions
   FILE functions
   LOG functions
   FAST SCREEN functions
   CRT functions
   TEXT functions
   CRC FUNCTIONS