c_gst_message_new_step_start

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)
GstMessage* function(GstObject* src, int active, GstFormat format, ulong amount, double rate, int flush, int intermediate) c_gst_message_new_step_start;

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