loc:
  create fname 256 allot
  : erase fname 256 0 fill ;
  here is use ] erase wsparse fname swap move ;
  variable #size              : size #blks @ 512 * #size ! ;

  from kernel32.dll
  1 import CloseHandle
  3 import OpenFile
  5 import ReadFile
  5 import WriteFile

  variable current
  : close current @ CloseHandle drop ;

  : open  fname here $0000 OpenFile current ! size ;
 :: open current @ there offset @ + #size @ here 0 ReadFile
    drop close ; is r

  : open fname here $1001 OpenFile current ! size ;
 :: open current @ there #size @ here 0 WriteFile drop close ; is w
;loc
