/sys$common/syshlp/helplib.hlb LSEDIT, Command Qualifiers, /CREATE  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  /CREATE (D)
  /NOCREATE

  Controls whether LSE creates a new file when the specified  input  file
  is not found.  By default, LSE provides a buffer in which to create the
  file.  When you exit from LSE or write out the contents of  the  buffer
  with the WRITE or COMPILE commands, LSE will create a new file with the
  input file specification in the appropriate directory.

  When you specify /NOCREATE on the LSE command  line  and  type  a  file
  specification  for  a  file  that  does  not exist, LSE prints an error
  message and returns you to DCL level.