I agree, and it seems to be a question that comes up frequently in
this forum, so maybe we should add a page to the Wiki that discusses
how to send and receive a stream of protobuf (or any) messages.
Things like run length encoding, magic bytes, checksums, record types
- these are either highly desirable or absolutely necessary when
streaming blocks of opaque binary data over a network connection,
reading a sequence of them from a file, or whatever.  I think there
may be a misconception out there that libprotobuf somehow magically
takes care of all those things.  It seems to me that people need to
conceive of a serialized protobuf object as the payload to a packet,
and it is their job to design a packet header that describes the
payload with sufficient information such that it can be extracted and
dispatched to the appropriate handler.


On Jan 12, 5:32 pm, Stuart Johnson <stu...@stu.org.uk> wrote:
> It's a good idea to send a delimiter as well, even if your end-to-end
> communication is considered reliable (TCP).  A software bug at ether end
> could cause you to loose sync.
> Use one byte as your "Start Byte" (0xaa for example) followed by the
> length of your message (can be a compressed integer).  When you receive
> a message, look for the Start byte (which should always be the first
> byte), decode the length, and then verify that you have all the bytes
> you need to decode the rest of the data.  Before you decode, verify that
> you have reached the end of the stream or that the next byte is the
> start of the next message.
> Kenton Varda wrote:
> > Send the size of the message first, then the data.
> > On Mon, Jan 12, 2009 at 4:34 PM, chongyc <chongy...@gmail.com
> > <mailto:chongy...@gmail.com>> wrote:
> >     When I send multiple messages, I should delimit them, and parse the
> >     buffer.
> >     What is the best way delimitting it  that you can recommend me ?
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