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Re: Simplify sendmmsg code
- From: Florian Weimer <fweimer at redhat dot com>
- To: Adhemerval Zanella <adhemerval dot zanella at linaro dot org>
- Cc: libc-alpha at sourceware dot org, "Joseph S. Myers" <joseph at codesourcery dot com>
- Date: Tue, 9 May 2017 22:28:20 +0200
- Subject: Re: Simplify sendmmsg code
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On 05/09/2017 08:41 PM, Adhemerval Zanella wrote:
I think we can add a sysdeps/posix sendmmsg based on sendmsg so we can
safely remove this macro usage on resolv code. I will work on this
after your patch inclusion.
The use of sendmmsg in the resolv code is problematic. We need to use
two separate sockets with different source ports to improve
compatibility anyway. This might also help firewalls with tearing down
state more quickly (single request/response very likely does not bump
the UDP timeout, but two requests and two responses might switch into
stream mode with a prolonged timeout; maybe that's why we originally hit
the Netfilter table overflow in some of the glibc resolver tests).
I'm not sure how quickly I will get to fixing this (I hope for 2.26), so
please do whatever you feel is necessary in the meantime.
Thanks,
Florian