Re: [lwip-users] recv function BLOCK because recv_mbox is full: can yougive me a solution?

[Jonathan Larmour]

Piero 74 wrote:
> 
> 
> 2008/3/7, Bill Auerbach <address@hidden
> <mailto:address@hidden>>:
> 
>     Should receive have blocked at all since there is data in the
>     recv_mbox?  Overflowing has no bearing on a thread waiting for data
>     when there is data already in the mbox.
> 
> 
> yes... it has blocked.... i tried to  use  a recv_mbox with more
> elemets, and the problem dosn't  happen... but  i'm thinking something
> to avoid this block...
> 
> i don't know if can help you to understand the problem, but i saw:
> 
> tcp fast timer was running and calling sys_mbox_trypost, but mbox was
> full... 

But that's the thing - if you have a recv blocked, then the mbox should not
be full.

lwip_recv calls netconn_recv which directly calls sys_arch_mbox_fetch to
receive pending data. If the mbox is full, then your thread should have
extracted data from the mbox immediately.

> so tcp_ip thread was running, but application task was
> blocked... in think in sys_arch_mbox_fetch (called with timeout =0) in
> netconn_recv.
> 
> Do you think could be usefull this:
> 
> enable LWIP_SO_RCVTIMEO
> set SO_RCVTIMEO option for a socket

I think you have a more fundamental problem with your mbox implementation.

Jifl
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