AF_UNIX/SOCK_DGRAM is dropping messages

Ken Brown
Thu Apr 15 15:01:40 GMT 2021

On 4/15/2021 9:15 AM, wrote:
> [snip]
>>> I tried SOCK_STREAM (and SOCK_SEQPACKET I think) for CYGWIN 3.2.0 but
>>> that didn't work at all
>>> As far as I understand, both all types on pretty much all
>>> implementations preserves message ordering though
>>> I haven't tried SOCK_STREAM and/or SOCK_SEQPACKET with the
>> topic/af_unix-branch. Is that worth a try ?
>> SOCK_STREAM is definitely worth a try.  The implementation of that should be
>> much more reliable than the implementation of SOCK_DGRAM at the
>> moment.  We don't implement SOCK_SEQPACKET.
> It might be a complete rewrite of our semantics though, because it's connection based and allows just one writer on each "channel" and messages (chunks) cannot be handled "atomically"

In that case, let's try to get the DGRAM case to work.  Corinna has already 
suggested (on cygwin-developers) a way to deal with the select issue I 
mentioned.  I'll make that change shortly.


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