[lwip-users] [lwip] Where to free the pbufs?

[Steve Reynolds]

Hi

I wonder if anyone can help me?

I am getting confused about where pbufs should be freed up.

I have written a simple tcp echo function which calls tcp_write without copy
to reflect anything that comes in. After a while it all hangs up and I think
the pbufs are
messed up.

The question is should I 

a) free the pbuf after the tcp_write?

or

b) free it in the output function of the interface

The problem is that I think the pbufs are freed in the stack when there is
an error. Also 
I notice that some of the TCP routines free the pbuf after calling ip_output
so that 
perhaps rules out b) ?

Have I missed something - is it OK to free pbufs twice?

_ we are using quite an old copy of the stack have there been recent changes
in this area?

Cheers

Steve
[This message was sent through the lwip discussion list.]