HEXCALC(1)                                        HEXCALC(1)
   
   
   
   NAME
       hexcalc - interactive hexadecimal calculator
   
   SYNOPSIS
       hexcalc
   
   DESCRIPTION
       Hexcalc reads standard input for a sequence of
       expressions and commands. Expressions are evaluated and
       the result is output in the default radix on standard
       output. Commands are executed, producing their defined
       action.
   
       Expressions are made up of the following operands and
       operators:
   
       Operands:       Numeric literals; in the default radix, 
                       must begin with a digit (for example, 
                       0cc01e).
   
                       Variables; initialized with an
                       assignment operation, 31 significant
                       chars max.
   
       Built-in functions:
             name            description
             ---------       -----------
             DEC(expr)       output decimal value of expr
             OCT(expr)       output octal value of expr
             HEX(expr)       output hex value of expr
   
       Operators (highest to lowest precedence):
             operator        description
             --------        -----------
             (  )            grouping
             **              exponentiation
             -  ~            unary minus, bitwise not
             *  /  %         multiplication, division, modulus
             +  -            addition, subtraction
             <<  >>          left-shift, right-shift
             &               bitwise and
             ^               bitwise exclusive-or
             |               bitwise or
             =               assignment
   
       The following commands are supported:
             name            description
             ----------      -----------
             help  HELP      print a help message
             quit  exit      terminate execution
             hex dec oct     set the default radix
   
       If assignment is the last operation performed when
       evaluating an expression, nothing is output.
   
       Hexcalc also recognizes and ignores comments. Comments
       begin with either a '#' character or a '##' character
       pair and are terminated by a newline. Comments beginning
       with a single '#' are called non- echoing and are
       completely ignored. Comments beginning with a '##' pair
       are called echoing comments and are output to stdout,
       beginning with the second '#', without modification.
       While comments make little sense when using hexcalc
       interactively, they can be used in files that are fed to
       stdin to good effect.
   
       The _rationale_ behind the current built-in functions is
       to allow the capture of intermediate results in the
       output stream as well as modifying the default radix for
       the results of expression evaluation. Note that they are
       functions which return the input value as a result so
       they can be used as operands in more complex
       expressions.
   
       The initial default radix is hexadecimal.
   
   NOTES
       Hexcalc is based on hoc3, a calculator program that can
       be found in _The Unix Programming Environment_ by Brian
       W. Kernighan and Rob Pike, chapter 8. The entire chapter
       is an exposition of a method of organizing a software
       development project which develops six different, and
       successively more complex, versions of hoc, a calculator
       program. It also serves as an excellent introduction to
       and tutorial for yacc(1).
   
   AUTHOR
       Richard Hargrove
       25 June 1988