On Monday, October 12, 2015, Erich E. Hoover <erich.e.hoover@wine-staging.com> wrote:

On Mon, Oct 12, 2015 at 9:16 AM, Erich E. Hoover
<erich.e.hoover@wine-staging.com> wrote:
> On Mon, Oct 12, 2015 at 1:25 AM, Alexandre Julliard <julliard@winehq.org> wrote:
>> "Erich E. Hoover" <erich.e.hoover@wine-staging.com> writes:
>>
>>> +�� /* set reasonable defaults when requested */
>>> +�� if (!bytes_per_send)
>>> +�� bytes_per_send = 1024;
>>
>> Is that the Windows default?�� It doesn't seem very reasonable to me, it
>> won't even fill a network packet.
>
> I don't know, it's not in the documentation.�� However, if you like I
> could try to tease it out by doing some tests and running Wireshark on
> it.�� I figured that since the default MTU is 1500 bytes that 1024
> would be a reasonable power of two less than that to use, but if you
> think that 2^16 is more reasonable then, obviously, we could use that
> instead.

Some googling suggests that this value is controlled by
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\AFD\Parameters\DefaultSendWindow
and that the default is different depending on the Windows version.
Apparently "normal" versions default to 64512 and server versions
default to 655360.�� How would you like this to be approached?

Hi all. What about reading SO_SNDBUF where it is available and 1024 where it is not. Because I think send() will fail if you try to write more than the kernel buffer size.