Hi,
> I think shared lock is useful. It requires additional work to change save
> handler interface and save handler code. It's a distinct feature from
> read_only. You can get status via session_status() if you need to know
> during execution. i.e. If session is started with read_only, you'll get
> PHP_SESSION_NONE status.
This is a bug.
A read-only session is not a non-existing session.
I'm thinking more of something like a SessionHandler::$isReadOnly property.
> I suppose read_only is good enough name for the feature. I appreciate better
> name for it, if there is.
It is a perfect name, no need to change it.
>
> Although I would not like to propose/implement the RFC now, but I may
> implement it if RFC passes.
Great, I'll count on that. :)