Struct IpcWriteMetadata 

struct IpcWriteMetadata {
    dictionary_block_sizes: Vec<(usize, usize)>,
    padded_header_len: usize,
    body_len: usize,
}

Per-message sizes produced by IpcDataGenerator::write.

FileWriter uses these to build the Block index entries required by the IPC footer for random-access reads.

Fields

dictionary_block_sizes: Vec<(usize, usize)>

Per-dictionary (padded_header_len, body_len) for each dictionary batch written before the record batch.

padded_header_len: usize

Flatbuffer header size including continuation prefix and alignment padding.

body_len: usize

Total length of the record-batch body including trailing alignment padding.