c_g_pollable_output_stream_write_nonblocking

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)
gssize function(GPollableOutputStream* stream, void* buffer, gsize count, GCancellable* cancellable, GError** error) c_g_pollable_output_stream_write_nonblocking;

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