Portable Character Processing in Fortran and Fixed Integer Environments

Many languages, including Fortran, and machines such as most minicomputers have little or no built-in character manipulation capability and yet are often required to process character information. This paper discusses the programming of character processing in such integer environments. Character representation, string-to-word coordinate transformation, packing, and unpacking using several arithmetic schemes are discussed with special attention to program portability. Several Fortran subroutines are presented culminating in BYTRAN, a set of portable Fortran subroutines that simulate the string structures and operators of the PL/I language.