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macOS doesn't have posix_fadvise(), but fcntl() with the F_RDADVISE command does the same thing. Some related documentation has been generalized to not mention posix_advise() specifically anymore. Reviewed-by: Thomas Munro <thomas.munro@gmail.com> Discussion: https://www.postgresql.org/message-id/flat/0827edec-1317-4917-a186-035eb1e3241d%40eisentraut.org