Purpose of streaming mode?

[regular]

Hi Dominic, just a question: What is the purpose of the streaming mode here? As I understand it, if you call reader.read() without a callback, what you get is essentially a transparent through stream, right? What is the use case for this?

Thanks,
Jan

[dominictarr]

I use that when I only need to read exact bytes in the header, and then the rest of the stream is handled another way. say, you could use pull-reader to check a magic number, and then divert the rest to an appropiate handler.

in particular i needed this to implement https://github.com/auditdrivencrypto/secret-handshake/
where a header is processed, then the rest of the stream handled by another module (hmm, which incidentially, also uses pull-reader...)

[dominictarr]

maybe I could have just passed the pull reader instance to pull-box-stream, but I implemented pull-box-stream first... and so this made it self contained.

[regular]

Interesting. I started work on a pull-stream with a readBits(n) API (pull-bits) (Need it to implement bzip2 decompression). It uses pull-reader internally, so I guess I'll just expose the switch-into-streaming-mode feature (asserting the current stream position is on a byte boundary).

Are you aware of a pre-existing module that does this, so I don't duplicate previous work?

Streaming mode in a bitstream pull-stream could be useful for implementing media de-muxers for formats with tightly packed, non-byte aligned frame header fields, or something.

[dominictarr]

I don't know about bzip2, but I know @chrisdickenson implemented zip in js for his git implementation. I don't know what came of that exactly though. the current git-js depends on https://github.com/nodeca/pako/ instead.