Library /sys$common/syshlp/lse$help.hlb SET_BUFFER_AUTO_ERASE  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  Syntax:  SET BUFFER AUTO ERASE boolean

  Enables or disables automatic erasing of placeholders for the current
  buffer.

  LSE erases the placeholder that the cursor is on when you type a
  character over that placeholder.  By default, this feature is active.

  RELATED COMMANDS:

     SET PLACEHOLDER commands    SHOW BUFFER