Re: [lwip-users] Struggling to build a TCP echo server

[Kieran Mansley]

On Fri, 2009-02-13 at 10:50 -0500, Chen wrote:
> First, thanks to all the helping hands from the group!
> 
> Weighing my options, I decided to use "real" socket programming
> instead of TCI_* raw APIs.
> 
> Attached is the codes of a working echo server, running on FreeRTOS.
> 
> After getting it to work, I tried to implement two echo servers on
> FreeRTOS. 
> 
> I duplicated the codes to a different thread, on a different port, and
> fired it up, none worked. It seems as long as I have one socket
> opened, the other will not be able to work.

Two things:

1) You should be very careful when using multiple threads with lwIP: it
is not thread-safe.

2) You may not have allocated enough PCBs to handle multiple
connections.  Check your lwipopts.h

Kieran