bug#23840: runemacs does not seem to pass command line arguments through to emacs properly

[Eliot Moss]

I use a Thunderbird add-on called "External Editor", that will invoke an
arbitrary editor program, passing on the command line the name of a file
to edit.  If I tell External Editor to use runemacs, the file is not
opened, and any underscores in the file name appear as spaces in the name
of the buffer.  I can ^X^F to the actual file, so the file is there, but
something in the runemacs->emacs transition seems to have converted
underscore to space in the file name.

OTOH, if I tell External Editor to use emacs instead of runemacs, the
proper file is opened but I get an annoying console window, too.

I've not been able to find any documentation on runemacs's command line
arguments, etc.  This suggests that it is intended to simply pass them
on unchanged emacs.  But something work than that seems to be happening.

Regards -- Eliot Moss
(Note: I am not subscribed to the list.)

(PS: I used to use Xemacs for this, but it is moribund and with Windows
10 exiting it causes Windows to think that it has crashed, popping up
two annoying windows that you have to dismiss to get back to Thunderbird.)