GtkThemingEngineClass.renderFrameGap

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
struct GtkThemingEngineClass
extern (C)
void function(GtkThemingEngine* engine, cairo_t* cr, double x, double y, double width, double height, GtkPositionType gapSide, double xy0_Gap, double xy1_Gap) renderFrameGap;

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