file: crc32.ml (* C implementation *) external crc32fast : Unix.file_descr -> int -> Int32.t = "caml_crc32" file: testcrc.ml | "fast" -> fun file -> let fd = Unix.openfile file [Unix.O_RDONLY] 0o644 in let sum = Crc32.crc32fast fd p.size in Unix.close fd; sum