udp(4) on OpenBSD
The text 22fb6310db5a, as OpenBSD 5.8, OpenBSD 5.7, OpenBSD 5.6, OpenBSD 5.5, OpenBSD 5.4, OpenBSD 5.3, OpenBSD 5.2, OpenBSD 5.1, OpenBSD 5.0, OpenBSD 4.9, OpenBSD 4.8, OpenBSD 4.7, OpenBSD 4.6, OpenBSD 4.5, OpenBSD 4.4, OpenBSD 4.3, OpenBSD 4.2 shipped it.
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