options usevc...

go list -deps -f {{.Dir}}
! stdout 'pkg[\\/]mod'

# v2 import should use a downloaded module
# both without an explicit go.mod entry ...
cp tmp/use_v2.go x.go
go get .
go list -deps -f {{.Dir}}
stdout 'pkg[\\/]mod[\\/]rsc.io[\\/]quote[\\/]v2@v2.0.1$'

# ... and with one ...
cp tmp/use_v2.mod go.mod
go list -deps -f {{.Dir}}
stdout 'pkg[\\/]mod[\\/]rsc.io[\\/]quote[\\/]v2@v2.0.1$'

					//  This option disables the behavior and makes glibc
					//  perform the IPv6 and IPv4 requests sequentially."
					conf.singleRequest = true
				case s == "use-vc" || s == "usevc" || s == "tcp":
					// Linux (use-vc), FreeBSD (usevc) and OpenBSD (tcp) option:
					// http://man7.org/linux/man-pages/man5/resolv.conf.5.html
					// "Sets RES_USEVC in _res.options.
					//  This option forces the use of TCP for DNS resolutions."

	b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) { b.AddBytes(payload) })
	return b.Bytes()
}

func computeAndUpdateOuterECHExtension(outer, inner *clientHelloMsg, ech *echContext, useKey bool) error {
	var encapKey []byte
	if useKey {
		encapKey = ech.encapsulatedKey
	}
	encodedInner, err := encodeInnerClientHello(inner, int(ech.config.MaxNameLength))
	if err != nil {
		return err
	}

			servers:  defaultNS,
			ndots:    1,
			useTCP:   true,
			timeout:  5 * time.Second,
			attempts: 2,
			search:   []string{"domain.local."},
		},
	},
	{
		name: "testdata/freebsd-usevc-resolv.conf",
		want: &dnsConfig{
			servers:  defaultNS,
			ndots:    1,
			useTCP:   true,
			timeout:  5 * time.Second,
			attempts: 2,
			search:   []string{"domain.local."},
		},
	},
	{