Re: [lwip-devel] lwip_recvfrom(sock == 0)

[address@hidden]

Am 26.09.2020 um 09:54 schrieb Gisle Vanem:
> goldsimon@gmx.de wrote:
>
>>> Now the MicroPython test hangs forever. Nothing happens
>>> with this socket 0. It's unconnected, so how could this socket
>>> ever receive a single byte?
>>
>> It should indeed not wait here, but return an error. Would you mind
>> adding a bug in our savannah bugtracker to ensure this does not get
>> forgotten?
>
> Done at:
>    https://savannah.nongnu.org/bugs/index.php?59182
>
>>> Could it be some of my 'LWIP_x' options are messed up?
>>
>> Hmm, while this could change with options, it still should not behave
>> like you saw.
> Adding a:
>    #define LWIP_SOCKET_OFFSET 100
>
> for a socket fd to start at 100, did not help.
> But it looks better than a socket 0. IMHO lwip_socket()
> returning 0 is highly confusing.

Why? File descriptors are >= 0. That's what the spec says:
https://pubs.opengroup.org/onlinepubs/009695399/functions/socket.html

Regards,
Simon