c_g_file_copy

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(GFile* source, GFile* destination, GFileCopyFlags flags, GCancellable* cancellable, GFileProgressCallback progressCallback, void* progressCallbackData, GError** err) c_g_file_copy;

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