Re: [lwip-users]send/receive urgent tcp-data

[address@hidden]

Bob Brusa wrote:
> Hi
> I have written a tiny lwip-based server-ap that sends and receives tcp  
> packages.
>
> When receiving data - how can I find out if this are normal or urgent  
> data? (or OOB=out of band data, as MS calls them).
> Similarely: How can I send a tcp-package with the urg-flag set?
> Thanks and best regards Robert
Unfortunately, lwIP currently does not process the urgent flag. The flag 
is present in the TCP header, but as there is no way to access the 
header in your recv callback, there's no way to get the TCP flags from 
that header.

Tx side is similar: lwIP creates the TCP header itself (cannot be 
directly influenced by the application) and there's currently no way to 
create a segment with the urgent flag.

Simon