diff --git a/vendor/golang.org/x/sys/unix/syscall.go b/vendor/golang.org/x/sys/unix/syscall.go
new file mode 100644
index 0000000..fd4ee8e
--- /dev/null
+++ b/vendor/golang.org/x/sys/unix/syscall.go
@@ -0,0 +1,53 @@
+// 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 contains an interface to the low-level operating system
+// primitives. OS details vary depending on the underlying system, and
+// by default, godoc will display OS-specific documentation for the current
+// system. If you want godoc to display OS documentation for another
+// system, set $GOOS and $GOARCH to the desired system. For example, if
+// you want to view documentation for freebsd/arm on linux/amd64, set $GOOS
+// to freebsd and $GOARCH to arm.
+//
+// The primary use of this package is inside other packages that provide a more
+// portable interface to the system, such as "os", "time" and "net".  Use
+// those packages rather than this one if you can.
+//
+// For details of the functions and data types in this package consult
+// the manuals for the appropriate operating system.
+//
+// These calls return err == nil to indicate success; otherwise
+// err represents an operating system error describing the failure and
+// holds a value of type syscall.Errno.
+package unix // import "golang.org/x/sys/unix"
+
+import "strings"
+
+// ByteSliceFromString returns a NUL-terminated slice of bytes
+// containing the text of s. If s contains a NUL byte at any
+// location, it returns (nil, EINVAL).
+func ByteSliceFromString(s string) ([]byte, error) {
+	if strings.IndexByte(s, 0) != -1 {
+		return nil, EINVAL
+	}
+	a := make([]byte, len(s)+1)
+	copy(a, s)
+	return a, nil
+}
+
+// BytePtrFromString returns a pointer to a NUL-terminated array of
+// bytes containing the text of s. If s contains a NUL byte at any
+// location, it returns (nil, EINVAL).
+func BytePtrFromString(s string) (*byte, error) {
+	a, err := ByteSliceFromString(s)
+	if err != nil {
+		return nil, err
+	}
+	return &a[0], nil
+}
+
+// Single-word zero for use when we need a valid pointer to 0 bytes.
+var _zero uintptr