[lwip-devel] lwIP freeing up resources

[Mahavir Jain]

Hi All,

We are using lwIP 1.4.1 release and I have below question related to lwIP stack
or rather in general about networking stack usage in low level embedded systems:

How do we make sure to release all allocated resources like connections or
sockets for particular thread/task in case we have to delete that particular
thread/task, assuming we are using blocking calls ? Timeout based recv, select 
is
something we would like to avoid to keep system in low power mode.

For example, consider a scenario where a thread acting as web server, is blocked
in accepted tcp connection on recv() call, and for some reason interface goes
down (or any other reason) and we have to re-start web server task. Another
thread deletes web-server task but what about socket/connection that is blocked
on recv(), and relevant resources in use ?

For systems where there is no such separation like user <--> kernel space how
this should be handled, i.e. to free up all resources once process is
deleted/killed ?

Any response in general or relevant to lwIP stack would be really helpful.

Mahavir