Re: SELECT() returns 1 But FIONREAD says (Input/output error)

[Uncle George <netbeans@gatworks.com>]

David Schwartz wrote:
> > David Schwartz wrote:
>
> > > Nope. An errored connection is always ready for read/write -- there is
> > > nothing to wait for as far as the kernel is concerned. Your code keeps
> > > asking the kernel if something interesting has happened, the
> > > kernel keeps
> > > telling it yes, and it refuses to do anything about it.
>
> > The select() returns because i pulled the USB cable from hub. Seems
> > reasonable.
>
> Good. Then there is nothing further to discuss.
>
> > The next select() found what? to be interesting in order to prematurely
> > terminate the select-wait? As far as I can tell, nothing interesting has
> > happened since the previous select(). In this case the select() is only
> > looking at read()'s.
>
> You have a very serious misunderstanding of what 'select' does. The 'select'
> function is level triggered and state based, not edge triggered or event
> based. The situation was the same as before, and so the same result is
> required.

The misunderstanding is from the docs.
The select() does not report device errors.
Select will just "more precisely, to see if a read will not block".



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