c_g_output_stream_write_all

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)
int function(GOutputStream* stream, void* buffer, size_t count, size_t* bytesWritten, GCancellable* cancellable, GError** err) c_g_output_stream_write_all;

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