References: golang.org/x/sys/unix.IPV6_USER

const golang.org/x/sys/unix.IPV6_USER_FLOW

one use

	golang.org/x/sys/unix (current package)
		ztypes_linux.go#L4149: 	IPV6_USER_FLOW = 0xe

The pages are generated with Golds v0.7.6. (GOOS=linux GOARCH=amd64)