a standard for the user's default terminal

[Marcos]

With xdg-open one can open every associated file and protocol with a mime assosiation on the
system.
Therefore one can type:

xdg-open /tmp/sample_text.txt
xdg-open /tmp/photo.jpg
xdg-open http://blah.com
xdg-open /tmp  ( it summons the file manager )

but... how can one open the default terminal ?
Is there a standard for this ? If not, don't we need one ?

Marcos Diez