Library /sys$common/syshlp/decw$helphelp.hlb Overview, Menus Edit, Menus Edit Select  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  The Select All menu item in the Edit menu is an easy
  way to select the whole of the current help topic. It
  can then be copied to the clipboard.

  Like Copy, this is useful for copying details into
  another application, for example to fill in a text
  block in a paint program, or to insert a detail into a
  Calendar meeting agenda.