pub fn minor_version() -> u32
Returns the minor version number of the GTK library.
For example, in GTK version 3.1.5 this is 1.
This function is in the library, so it represents the GTK library
your code is are running against. Contrast with the
GTK_MINOR_VERSION macro, which represents the minor version of the
GTK headers you have included when compiling your code.
the minor version number of the GTK library