LLT (string-a, string-b)

  Class:  Elemental function - Generic

  Returns a value of true if the first character string is less than
  the second character string, based on the ASCII collating sequence
  - even if the processor's default collating sequence is different.
  In VSI Fortran, LLT is equivalent to the < operator.

  The ASCII collating sequence determines the relationship between
  the arguments.

  The arguments must be character expressions.  The result is a
  LOGICAL*4 value.

  This function cannot be passed as an actual argument.