c_gst_app_sink_set_callbacks

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(GstAppSink* appsink, GstAppSinkCallbacks* callbacks, void* userData, GDestroyNotify notify) c_gst_app_sink_set_callbacks;

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