Re: [lwip-users] socket & select: can i use select with socket in listen mode?

[Jonathan Larmour]

Piero 74 wrote:
> 
> I read in BSD socket application note, that i can use select to manage
> IO form multiple sockets, using timeout, so, without blocking calls.
> 
> The example shows this idea:
> 
> 1. create tcp socket in listen mode
> 2. use select with sd of this socket to wait new connection using
> timeout and loop.
> 3. if new connection is available, accept it using new socket, set
> select for wait both new connection from the first socket and data from
> second, without block.
> 
> this idea allows to wait data from connected socket and wait new
> connections withou block in accept call.

Yes this is meant to work.

> i saw that option FIONBIO in lwip doesn't have effect in accept call,

Correct.

> so, this idea could be usefull for non-blocking io with listen socket

Indeed if you already know there's a pending connection (because select has
returned with that fd marked readable), then accept will not block.

> Do you know if lwip implementation of select allows this idea?

Yes.

Jifl
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