/EXTRACT=filename.MSGHLP
Extracts messages from the database and generates a .MSGHLP file
that can be edited, if desired, and used as input for /INSERT and
/DELETE operations. /EXTRACT retrieves data from a .MSGHLP$DATA
file or logical search path specified by /LIBRARY or, by default,
from files in the search path defined by logical name MSGHLP$LIBRARY.
When /EXTRACT is not specified, Help Message produces output in
standard text format by default (see /OUTPUT).