> is there a standard 'stdin' and/or 'stdout' "name", e.g. the '-' in perl?
I
> see a reference to something like it when using "Kernel.open('|-')" ---
but
> this seems to be the only/special case?

The Ruby interpreter defines three global IO objects:

    $stdin
    $stdout
    $stderr

as the *current* standard input/output/error for Ruby (which is to say they
can be reassigned). The original (constant) IO streams are also stored as
STDIN, STDOUT and STDERR.

Hope this helps,

Lyle