procedure AppendFile(var GdInput : boolean;
                    OutPath      : string;
                    WhatFile     : string;
                    var OutFile  : Data);
begin
  gdinput := true;
  if Exist(Outpath+Whatfile) then
    begin
      assign (outfile,outpath+whatfile);
      append(OutFile);
    end  {if exist...}
  else
    begin
      assign (Outfile, outpath+whatfile);
{$I-} rewrite(OutFile);                                       {$I+}
      if (ioresult <> 0) then
        begin
          Error('Bad filename!  Re-enter the complete filename including path.');
          GdInput := False;
        end;
    end; {else}
end;