Library /sys$common/syshlp/ncphelp.hlb Prompting, Format of prompts  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 The component part indicates the name of either the component or
 parameter.  The format part indicates the range of acceptable values.
 The format part presents keywords in uppercase, value classes in
 lowercase as descriptive strings, and numeric ranges as two numbers
 separated by a hyphen.  Commas indicate alternatives which are mutually
 exclusive.