[cfarm-users] Max UDP dgram size on M1 machine (gcc304)

Kaz Kylheku kaz at kylheku.com
Thu Mar 25 01:04:30 CET 2021

On 2021-03-24 13:45, Bruno Haible wrote:
> Hi Kaz,
>> On Mac OS, there are, by default, bizarre restrictions on IP datagram
>> sizes
>> in the protocol stack.
>> ...
>> I have a test case involving UDP that works on numerous platforms, the
>> oddball being MacOS
> So, the test machine was useful to you: it has told you that a test 
> case
> (and presumably also some functionality of your package) is not working
> on stock macOS.

Hi Bruno. Well, it's not the case that I'm newly informed. The test case
is years old, and so is that issue. I've carried that workaround in a
MacOS VM for ages. The package doesn't need it; it's library code.

I see your point that it's unnecessary and wrongheaded; I can instead
fix the test case to still usefully execute on MacOS, but not to
generate an excessive datagram size.

I do have tests that are modified or disabled on some platforms.

For instance Cygwin permissions have started acting up for me in 
in nonsensical ways, so various chmod tests can't work. Certain FFI
tests need alternative struct definitions, or can't work at all,
and things like that.

More information about the cfarm-users mailing list