select-enable-clipboard

select-enable-clipboard is a variable defined in `select.el'.
Its value is

t

Documentation:
Non-nil means cutting and pasting uses the clipboard.
This can be in addition to, but in preference to, the primary selection,
if applicable (i.e. under X11).

You can customize this variable.

This variable was introduced, or its default value was changed, in version 24.1 of Emacs.