Re: [lwip-users] questions on lwip (two TCP/IP sockets)

[address@hidden]

 Kieran Mansley wrote:
> On 12 Aug 2010, at 20:16, Jeff Barber wrote:
>
> > I'd like to see someone more authoritative (like Simon or Kieran?)
> > weigh in on this but I'm pretty sure that the advice you cited is just
> > plain wrong.
> Yes, it's very wrong.  It may once have been true in the dim past,
Hmm, "dim past"... that post seems to be only less than 2 months old, 
however, I don't remember having read it or I would have told the author 
that it's wrong...
>   but even so it references memory after it was freed
And that's the point at which I'm really confused: Either our 
documentation is really really bad or the author of that post should 
first start programming with something easier than lwIP... accessing 
freed memory seems like a beginner's mistake to me (sorry if this sounds 
rude!), and (unfortunately) lwIP is a bit more complicated to handle 
than a simple "hello world" example :-(

Anyway:
1) pbuf_free() on the pbuf passed in is definitively the right thing to 
do (there are ways how to call pbuf_free on every single pbuf in a 
chain, but that involves more code and is not really advised)... and
2) please start from the existing examples in contrib: most of them are 
correct, and if they aren't we can fix them. Just starting from 
something you read somewhere isn't a good idea as you never know who 
wrote that and if it is correct...

BTW: Jeff, I don't think you really need our opinion on this as I fully 
agree to everything you wrote ;-)

Simon