diff --git a/vendor/golang.org/x/sys/unix/syscall_unix.go b/vendor/golang.org/x/sys/unix/syscall_unix.go
new file mode 100644
index 0000000..3de3756
--- /dev/null
+++ b/vendor/golang.org/x/sys/unix/syscall_unix.go
@@ -0,0 +1,431 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris
+
+package unix
+
+import (
+	"bytes"
+	"sort"
+	"sync"
+	"syscall"
+	"unsafe"
+)
+
+var (
+	Stdin  = 0
+	Stdout = 1
+	Stderr = 2
+)
+
+// Do the interface allocations only once for common
+// Errno values.
+var (
+	errEAGAIN error = syscall.EAGAIN
+	errEINVAL error = syscall.EINVAL
+	errENOENT error = syscall.ENOENT
+)
+
+var (
+	signalNameMapOnce sync.Once
+	signalNameMap     map[string]syscall.Signal
+)
+
+// errnoErr returns common boxed Errno values, to prevent
+// allocations at runtime.
+func errnoErr(e syscall.Errno) error {
+	switch e {
+	case 0:
+		return nil
+	case EAGAIN:
+		return errEAGAIN
+	case EINVAL:
+		return errEINVAL
+	case ENOENT:
+		return errENOENT
+	}
+	return e
+}
+
+// ErrnoName returns the error name for error number e.
+func ErrnoName(e syscall.Errno) string {
+	i := sort.Search(len(errorList), func(i int) bool {
+		return errorList[i].num >= e
+	})
+	if i < len(errorList) && errorList[i].num == e {
+		return errorList[i].name
+	}
+	return ""
+}
+
+// SignalName returns the signal name for signal number s.
+func SignalName(s syscall.Signal) string {
+	i := sort.Search(len(signalList), func(i int) bool {
+		return signalList[i].num >= s
+	})
+	if i < len(signalList) && signalList[i].num == s {
+		return signalList[i].name
+	}
+	return ""
+}
+
+// SignalNum returns the syscall.Signal for signal named s,
+// or 0 if a signal with such name is not found.
+// The signal name should start with "SIG".
+func SignalNum(s string) syscall.Signal {
+	signalNameMapOnce.Do(func() {
+		signalNameMap = make(map[string]syscall.Signal)
+		for _, signal := range signalList {
+			signalNameMap[signal.name] = signal.num
+		}
+	})
+	return signalNameMap[s]
+}
+
+// clen returns the index of the first NULL byte in n or len(n) if n contains no NULL byte.
+func clen(n []byte) int {
+	i := bytes.IndexByte(n, 0)
+	if i == -1 {
+		i = len(n)
+	}
+	return i
+}
+
+// Mmap manager, for use by operating system-specific implementations.
+
+type mmapper struct {
+	sync.Mutex
+	active map[*byte][]byte // active mappings; key is last byte in mapping
+	mmap   func(addr, length uintptr, prot, flags, fd int, offset int64) (uintptr, error)
+	munmap func(addr uintptr, length uintptr) error
+}
+
+func (m *mmapper) Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) {
+	if length <= 0 {
+		return nil, EINVAL
+	}
+
+	// Map the requested memory.
+	addr, errno := m.mmap(0, uintptr(length), prot, flags, fd, offset)
+	if errno != nil {
+		return nil, errno
+	}
+
+	// Slice memory layout
+	var sl = struct {
+		addr uintptr
+		len  int
+		cap  int
+	}{addr, length, length}
+
+	// Use unsafe to turn sl into a []byte.
+	b := *(*[]byte)(unsafe.Pointer(&sl))
+
+	// Register mapping in m and return it.
+	p := &b[cap(b)-1]
+	m.Lock()
+	defer m.Unlock()
+	m.active[p] = b
+	return b, nil
+}
+
+func (m *mmapper) Munmap(data []byte) (err error) {
+	if len(data) == 0 || len(data) != cap(data) {
+		return EINVAL
+	}
+
+	// Find the base of the mapping.
+	p := &data[cap(data)-1]
+	m.Lock()
+	defer m.Unlock()
+	b := m.active[p]
+	if b == nil || &b[0] != &data[0] {
+		return EINVAL
+	}
+
+	// Unmap the memory and update m.
+	if errno := m.munmap(uintptr(unsafe.Pointer(&b[0])), uintptr(len(b))); errno != nil {
+		return errno
+	}
+	delete(m.active, p)
+	return nil
+}
+
+func Read(fd int, p []byte) (n int, err error) {
+	n, err = read(fd, p)
+	if raceenabled {
+		if n > 0 {
+			raceWriteRange(unsafe.Pointer(&p[0]), n)
+		}
+		if err == nil {
+			raceAcquire(unsafe.Pointer(&ioSync))
+		}
+	}
+	return
+}
+
+func Write(fd int, p []byte) (n int, err error) {
+	if raceenabled {
+		raceReleaseMerge(unsafe.Pointer(&ioSync))
+	}
+	n, err = write(fd, p)
+	if raceenabled && n > 0 {
+		raceReadRange(unsafe.Pointer(&p[0]), n)
+	}
+	return
+}
+
+// For testing: clients can set this flag to force
+// creation of IPv6 sockets to return EAFNOSUPPORT.
+var SocketDisableIPv6 bool
+
+// Sockaddr represents a socket address.
+type Sockaddr interface {
+	sockaddr() (ptr unsafe.Pointer, len _Socklen, err error) // lowercase; only we can define Sockaddrs
+}
+
+// SockaddrInet4 implements the Sockaddr interface for AF_INET type sockets.
+type SockaddrInet4 struct {
+	Port int
+	Addr [4]byte
+	raw  RawSockaddrInet4
+}
+
+// SockaddrInet6 implements the Sockaddr interface for AF_INET6 type sockets.
+type SockaddrInet6 struct {
+	Port   int
+	ZoneId uint32
+	Addr   [16]byte
+	raw    RawSockaddrInet6
+}
+
+// SockaddrUnix implements the Sockaddr interface for AF_UNIX type sockets.
+type SockaddrUnix struct {
+	Name string
+	raw  RawSockaddrUnix
+}
+
+func Bind(fd int, sa Sockaddr) (err error) {
+	ptr, n, err := sa.sockaddr()
+	if err != nil {
+		return err
+	}
+	return bind(fd, ptr, n)
+}
+
+func Connect(fd int, sa Sockaddr) (err error) {
+	ptr, n, err := sa.sockaddr()
+	if err != nil {
+		return err
+	}
+	return connect(fd, ptr, n)
+}
+
+func Getpeername(fd int) (sa Sockaddr, err error) {
+	var rsa RawSockaddrAny
+	var len _Socklen = SizeofSockaddrAny
+	if err = getpeername(fd, &rsa, &len); err != nil {
+		return
+	}
+	return anyToSockaddr(fd, &rsa)
+}
+
+func GetsockoptByte(fd, level, opt int) (value byte, err error) {
+	var n byte
+	vallen := _Socklen(1)
+	err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen)
+	return n, err
+}
+
+func GetsockoptInt(fd, level, opt int) (value int, err error) {
+	var n int32
+	vallen := _Socklen(4)
+	err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen)
+	return int(n), err
+}
+
+func GetsockoptInet4Addr(fd, level, opt int) (value [4]byte, err error) {
+	vallen := _Socklen(4)
+	err = getsockopt(fd, level, opt, unsafe.Pointer(&value[0]), &vallen)
+	return value, err
+}
+
+func GetsockoptIPMreq(fd, level, opt int) (*IPMreq, error) {
+	var value IPMreq
+	vallen := _Socklen(SizeofIPMreq)
+	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
+	return &value, err
+}
+
+func GetsockoptIPv6Mreq(fd, level, opt int) (*IPv6Mreq, error) {
+	var value IPv6Mreq
+	vallen := _Socklen(SizeofIPv6Mreq)
+	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
+	return &value, err
+}
+
+func GetsockoptIPv6MTUInfo(fd, level, opt int) (*IPv6MTUInfo, error) {
+	var value IPv6MTUInfo
+	vallen := _Socklen(SizeofIPv6MTUInfo)
+	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
+	return &value, err
+}
+
+func GetsockoptICMPv6Filter(fd, level, opt int) (*ICMPv6Filter, error) {
+	var value ICMPv6Filter
+	vallen := _Socklen(SizeofICMPv6Filter)
+	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
+	return &value, err
+}
+
+func GetsockoptLinger(fd, level, opt int) (*Linger, error) {
+	var linger Linger
+	vallen := _Socklen(SizeofLinger)
+	err := getsockopt(fd, level, opt, unsafe.Pointer(&linger), &vallen)
+	return &linger, err
+}
+
+func GetsockoptTimeval(fd, level, opt int) (*Timeval, error) {
+	var tv Timeval
+	vallen := _Socklen(unsafe.Sizeof(tv))
+	err := getsockopt(fd, level, opt, unsafe.Pointer(&tv), &vallen)
+	return &tv, err
+}
+
+func GetsockoptUint64(fd, level, opt int) (value uint64, err error) {
+	var n uint64
+	vallen := _Socklen(8)
+	err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen)
+	return n, err
+}
+
+func Recvfrom(fd int, p []byte, flags int) (n int, from Sockaddr, err error) {
+	var rsa RawSockaddrAny
+	var len _Socklen = SizeofSockaddrAny
+	if n, err = recvfrom(fd, p, flags, &rsa, &len); err != nil {
+		return
+	}
+	if rsa.Addr.Family != AF_UNSPEC {
+		from, err = anyToSockaddr(fd, &rsa)
+	}
+	return
+}
+
+func Sendto(fd int, p []byte, flags int, to Sockaddr) (err error) {
+	ptr, n, err := to.sockaddr()
+	if err != nil {
+		return err
+	}
+	return sendto(fd, p, flags, ptr, n)
+}
+
+func SetsockoptByte(fd, level, opt int, value byte) (err error) {
+	return setsockopt(fd, level, opt, unsafe.Pointer(&value), 1)
+}
+
+func SetsockoptInt(fd, level, opt int, value int) (err error) {
+	var n = int32(value)
+	return setsockopt(fd, level, opt, unsafe.Pointer(&n), 4)
+}
+
+func SetsockoptInet4Addr(fd, level, opt int, value [4]byte) (err error) {
+	return setsockopt(fd, level, opt, unsafe.Pointer(&value[0]), 4)
+}
+
+func SetsockoptIPMreq(fd, level, opt int, mreq *IPMreq) (err error) {
+	return setsockopt(fd, level, opt, unsafe.Pointer(mreq), SizeofIPMreq)
+}
+
+func SetsockoptIPv6Mreq(fd, level, opt int, mreq *IPv6Mreq) (err error) {
+	return setsockopt(fd, level, opt, unsafe.Pointer(mreq), SizeofIPv6Mreq)
+}
+
+func SetsockoptICMPv6Filter(fd, level, opt int, filter *ICMPv6Filter) error {
+	return setsockopt(fd, level, opt, unsafe.Pointer(filter), SizeofICMPv6Filter)
+}
+
+func SetsockoptLinger(fd, level, opt int, l *Linger) (err error) {
+	return setsockopt(fd, level, opt, unsafe.Pointer(l), SizeofLinger)
+}
+
+func SetsockoptString(fd, level, opt int, s string) (err error) {
+	var p unsafe.Pointer
+	if len(s) > 0 {
+		p = unsafe.Pointer(&[]byte(s)[0])
+	}
+	return setsockopt(fd, level, opt, p, uintptr(len(s)))
+}
+
+func SetsockoptTimeval(fd, level, opt int, tv *Timeval) (err error) {
+	return setsockopt(fd, level, opt, unsafe.Pointer(tv), unsafe.Sizeof(*tv))
+}
+
+func SetsockoptUint64(fd, level, opt int, value uint64) (err error) {
+	return setsockopt(fd, level, opt, unsafe.Pointer(&value), 8)
+}
+
+func Socket(domain, typ, proto int) (fd int, err error) {
+	if domain == AF_INET6 && SocketDisableIPv6 {
+		return -1, EAFNOSUPPORT
+	}
+	fd, err = socket(domain, typ, proto)
+	return
+}
+
+func Socketpair(domain, typ, proto int) (fd [2]int, err error) {
+	var fdx [2]int32
+	err = socketpair(domain, typ, proto, &fdx)
+	if err == nil {
+		fd[0] = int(fdx[0])
+		fd[1] = int(fdx[1])
+	}
+	return
+}
+
+var ioSync int64
+
+func CloseOnExec(fd int) { fcntl(fd, F_SETFD, FD_CLOEXEC) }
+
+func SetNonblock(fd int, nonblocking bool) (err error) {
+	flag, err := fcntl(fd, F_GETFL, 0)
+	if err != nil {
+		return err
+	}
+	if nonblocking {
+		flag |= O_NONBLOCK
+	} else {
+		flag &= ^O_NONBLOCK
+	}
+	_, err = fcntl(fd, F_SETFL, flag)
+	return err
+}
+
+// Exec calls execve(2), which replaces the calling executable in the process
+// tree. argv0 should be the full path to an executable ("/bin/ls") and the
+// executable name should also be the first argument in argv (["ls", "-l"]).
+// envv are the environment variables that should be passed to the new
+// process (["USER=go", "PWD=/tmp"]).
+func Exec(argv0 string, argv []string, envv []string) error {
+	return syscall.Exec(argv0, argv, envv)
+}
+
+// Lutimes sets the access and modification times tv on path. If path refers to
+// a symlink, it is not dereferenced and the timestamps are set on the symlink.
+// If tv is nil, the access and modification times are set to the current time.
+// Otherwise tv must contain exactly 2 elements, with access time as the first
+// element and modification time as the second element.
+func Lutimes(path string, tv []Timeval) error {
+	if tv == nil {
+		return UtimesNanoAt(AT_FDCWD, path, nil, AT_SYMLINK_NOFOLLOW)
+	}
+	if len(tv) != 2 {
+		return EINVAL
+	}
+	ts := []Timespec{
+		NsecToTimespec(TimevalToNsec(tv[0])),
+		NsecToTimespec(TimevalToNsec(tv[1])),
+	}
+	return UtimesNanoAt(AT_FDCWD, path, ts, AT_SYMLINK_NOFOLLOW)
+}