

OPEN keywords

The current situation, in which file systems barf at keywords that they
don't know how to handle, seems more reasonable to me than having them
be ignored.  However, before a special thing is done for OPEN, may I
suggest that there are many places in message passing where a single
message comes in more than one "mode".  A rather limited analogy is in
the window system, where :READ/SET-CURSORPOS comes in :CHARACTERS and
:PIXEL modes.  Not all :READ/SET-CURSORPOS messages might come in both
modes, however, and it might be worthwhile to come up with a general way
of determining whether a mode is supported.  One can also imagine a
"tree" message passing structure, where modes have submodes, etc.

Barring that, both RMS's suggestion of :OPEN-KEYWORD-HANDLED-P and
Moon's suggestion of a global list of ignorable open keywords are OK
with me.