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Real2Double function

In unit System

Convert Turbo Pascal style real to double.

Declaration

pascal
function Real2Double(r: Real48): Double

Description

The Real2Double function converts a Turbo Pascal style real (6 bytes long) to a native Free Pascal double type. It can be used e.g. to read old binary TP files with FPC and convert them to Free Pascal binary files.

Note that the assignment operator has been overloaded so a Real48 type can be assigned directly to a double or extended.

Errors

None.

Example: ex110

pascal
program Example110;

{ Program to demonstrate the Real2Double function. }

Var
  i : integer;
  R : Real48;
  D : Double;
  E : Extended;
  F : File of Real48;

begin
  Assign(F,'reals.dat');
  Reset(f);
  For I:=1 to 10 do
    begin
    Read(F,R);
    D:=Real2Double(R);
    Writeln('Real ',i,' : ',D);
    D:=R;
    Writeln('Real (direct to double)  ',i,' : ',D);
    E:=R;
    Writeln('Real (direct to Extended) ',i,' : ',E);
    end;
  Close(f);
end.

An experiment, built from development snapshots. Not the official Free Pascal or Lazarus documentation.