c_gtk_render_frame_gap

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
__gshared extern (C)
void function(GtkStyleContext* context, cairo_t* cr, gdouble x, gdouble y, gdouble width, gdouble height, GtkPositionType gapSide, gdouble xy0_Gap, gdouble xy1_Gap) c_gtk_render_frame_gap;

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