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Date: Mon, 21 Sep 2015 18:45:48 +1000
Subject: Re: Lightwight socket IO wrapper
From: Chris Angelico <rosuav@gmail.com>
To: Marko Rauhamaa <marko@pacujo.net>
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On Mon, Sep 21, 2015 at 6:38 PM, Marko Rauhamaa <marko@pacujo.net> wrote:
> Chris Angelico <rosuav@gmail.com>:
>
>> On Mon, Sep 21, 2015 at 5:59 PM, Marko Rauhamaa <marko@pacujo.net> wrote:
>>> You can read a full buffer even if you have a variable-length length
>>> encoding.
>>
>> Not sure what you mean there. Unless you can absolutely guarantee that
>> you didn't read too much, or can absolutely guarantee that your
>> buffering function will be the ONLY way anything reads from the
>> socket, buffering is a problem.
>
> Only one reader can read a socket safely at any given time so mutual
> exclusion is needed.
>
> If you read "too much," the excess can be put in the application's read
> buffer where it is available for whoever wants to process the next
> message.

Which works only if you have a single concept of "application's read
buffer". That means that you have only one place that can ever read
data. Imagine a