2.1 D-Bus version.

D-Bus has evolved over the years. New features have been added with new D-Bus versions. There are two variables, which allow the determination of the D-Bus version used.

Variable: dbus-compiled-version ¶

This variable, a string, determines the version of D-Bus Emacs is compiled against. If it cannot be determined the value is nil.

Variable: dbus-runtime-version ¶

The other D-Bus version to be checked is the version of D-Bus Emacs runs with. This string can be different from dbus-compiled-version. It is also nil, if it cannot be determined at runtime.