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IO Module OCTET

DEFINITION MODULE OCTET;

(* I/O Module for Type OCTET *)

FROM FileIO IMPORT File;

(* EBNF of the textual representation of OCTET values:
    octetValue : simpleFormat |
        cBase16Format | m2Base2Format | m2Base16Format ;
    simpleFormat : base16Digit base16Digit ;
    cBase16Format : "0x" simpleFormat ;
    m2Base16Format : "0" simpleFormat "H" ;
    m2Base2Format : bit bit bit bit bit bit bit bit "B" ;
    base16Digit : "0" .. "9" | "A" .. "F" ;
    bit : "0" | "1" ; *)

PROCEDURE Read ( infile : File; VAR n : OCTET );
(* Reads the textual representation of an OCTET value from stream infile
   - any leading whitespace is skipped
   - any remaining characters that are part of the value being read are
     removed from infile
   - the textual representation of the value read is assigned to n
   - the file status is set to any of:
     success, outOfRange, wrongFormat, endOfLine, or endOfInput. This
   procedure is substituted for invocations of READ with an OCTET argument. *)

PROCEDURE Write ( outfile : File; n : OCTET );
(* Writes the value of OCTET n in simple format to stream outfile. This
   procedure is substituted for invocations of WRITE with an OCTET argument.*)

PROCEDURE WriteF ( outfile      : File;
                   CONST fmtStr : ARRAY OF CHAR;
                   items        : VARIADIC OF OCTET );
(* Writes a formatted textual representation of one or more OCTET values to
   output stream outfile. The output format is determined by fmtStr. This
   procedure is substituted for invocations of WRITEF with one or more
   OCTET arguments. *)

END OCTET.