Class type Mapred_io.record_reader

class type record_reader = object .. end

method pos_in : int

The ordinal number of the record that will be read next. Numbers start at 0

method input_record : unit -> string

Reads one record, and advances the cursor. May raise End_of_file

method peek_record : unit -> string

Reads the record, but does not advance the cursor, i.e. the next peek_record or input_record will read the line again. May raise End_of_file.

method input_records : string Queue.t -> unit

Reads some records and appends them to the passed queue. It is at least one records read. Will raise End_of_file if the end of the file is reached.

method close_in : unit -> unit

Releases resources (e.g. closes transactions)

method abort : unit -> unit

Drops resources - intended to be used for error cleanup

method to_fd_e : Unix.file_descr -> unit Uq_engines.engine

to_fd_e fd: The records are written to fd. The position pos_in is not updated. The length of the records is not checked except for a few records that are crucial for interpreting the boundaries of the bigblocks.

One should only either use to_fd_e or input_record. When mixing both styles, it is undefined which data is read by which method.

While the engine is running no other method must be called.

method to_any_e : (Netsys_mem.memory -> int -> int -> unit Uq_engines.engine) ->
       unit Uq_engines.engine

to_any_e dest: like to_fd_e but the data is not written to a file descriptor. Instead, the function dest is called like dest m pos len to output some data.

This is an experimental method! It might not be defined on every record reader.

method plasma_cluster : Plasma_client.plasma_cluster

The PlasmaFS cluster

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