Repository navigation
net: inconsistent SO_BROADCAST setting on dual-stack IPv6 sockets between platforms #81259
Description
On Linux and macOS, you can open a UDP socket listening on the unspecified address, and send a broadcast packet by writing a packet to 255.255.255.255.
This also used to work on Windows, but stopped working after CL 232807, which gated SO_BROADCAST behind IPv4 UDP sockets, citing Microsoft's documentation as the reason. This was actually a misinterpretation. SO_BROADCAST does not apply to IPv6 traffic, but it can be set on all IPv6 UDP sockets, and it will apply to IPv4 UDP packets, if IPV6_V6ONLY is set to 0.
I sent CL 804662 back in July, but it's not getting any reviews or comments, so I'm opening this issue to track it.
Activity
gabyhelp commentedon Aug 31, 2026
Related Code Changes
(Emoji vote if this was helpful or unhelpful; more detailed feedback welcome in this discussion.)
gopherbot commentedon Aug 31, 2026
Change https://go.dev/cl/804662 mentions this issue:
net: re-enable SO_BROADCAST on IPv6 UDP sockets on Windowsprattmic commentedon Sep 4, 2026
cc @ianlancetaylor @neild @nicholashusin @golang/windows
net: re-enable SO_BROADCAST on dual-stack IPv6 UDP sockets on Windows