GBufferedInputStreamClass.fillAsync

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
struct GBufferedInputStreamClass
extern (C)
void function(GBufferedInputStream* stream, ptrdiff_t count, int ioPriority, GCancellable* cancellable, GAsyncReadyCallback callback, void* userData) fillAsync;

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