RE: [lwip-devel] ethernetif.c HANDLE error

[Pettinato, Jim]

Jonathan, Piero:

It is my understanding that NO checking is done on the return value of 
low_level_output()... it looks to me like the return value is passed back up 
the call chain and then eventually ignored by tcp_output. I think you could 
return ERR_END_OF_THE_WORLD_IS_AT_HAND without effect. ;)

Am I mistaken perhaps?

- Jim
 

> Hi all!
> 
> just a question:
> 
> if i have some strange problem in my EMAC driver OR simply the link is 
> off (cable is unplugged), my implementattion of low_level_output 
> return ERR_IF
> 
> Is it correct or it could be a problem?

-----Original Message-----
From: address@hidden [mailto:address@hidden On Behalf Of Jonathan Larmour
Sent: Wednesday, February 20, 2008 10:40 AM
To: lwip-devel
Subject: Re: [lwip-devel] ethernetif.c HANDLE error


ERR_IF is a fatal error. If lwIP encounters that when sending data, the 
associated sockets/connections will get forcibly closed. It's up to you 
(through your driver implementation) if that's what you want.

Normally the link going away (e.g. cable unplugged) is considered a temporary 
failure, and not one to cause connections to be dropped. Perhaps that driver 
should be changed.

Jifl
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