diff --git a/unix/syscall_bsd.go b/unix/syscall_bsd.go
index 9679dec8..e9671764 100644
--- a/unix/syscall_bsd.go
+++ b/unix/syscall_bsd.go
@@ -450,16 +450,34 @@ func Kevent(kq int, changes, events []Kevent_t, timeout *Timespec) (n int, err e
 
 //sys	sysctl(mib []_C_int, old *byte, oldlen *uintptr, new *byte, newlen uintptr) (err error) = SYS___SYSCTL
 
-func Sysctl(name string) (value string, err error) {
+// sysctlmib translates name to mib number and appends any additional args.
+func sysctlmib(name string, args ...int) ([]_C_int, error) {
 	// Translate name to mib number.
 	mib, err := nametomib(name)
+	if err != nil {
+		return nil, err
+	}
+
+	for _, a := range args {
+		mib = append(mib, _C_int(a))
+	}
+
+	return mib, nil
+}
+
+func Sysctl(name string) (string, error) {
+	return SysctlArgs(name)
+}
+
+func SysctlArgs(name string, args ...int) (string, error) {
+	mib, err := sysctlmib(name, args...)
 	if err != nil {
 		return "", err
 	}
 
 	// Find size.
 	n := uintptr(0)
-	if err = sysctl(mib, nil, &n, nil, 0); err != nil {
+	if err := sysctl(mib, nil, &n, nil, 0); err != nil {
 		return "", err
 	}
 	if n == 0 {
@@ -468,7 +486,7 @@ func Sysctl(name string) (value string, err error) {
 
 	// Read into buffer of that size.
 	buf := make([]byte, n)
-	if err = sysctl(mib, &buf[0], &n, nil, 0); err != nil {
+	if err := sysctl(mib, &buf[0], &n, nil, 0); err != nil {
 		return "", err
 	}
 
@@ -479,17 +497,19 @@ func Sysctl(name string) (value string, err error) {
 	return string(buf[0:n]), nil
 }
 
-func SysctlUint32(name string) (value uint32, err error) {
-	// Translate name to mib number.
-	mib, err := nametomib(name)
+func SysctlUint32(name string) (uint32, error) {
+	return SysctlUint32Args(name)
+}
+
+func SysctlUint32Args(name string, args ...int) (uint32, error) {
+	mib, err := sysctlmib(name, args...)
 	if err != nil {
 		return 0, err
 	}
 
-	// Read into buffer of that size.
 	n := uintptr(4)
 	buf := make([]byte, 4)
-	if err = sysctl(mib, &buf[0], &n, nil, 0); err != nil {
+	if err := sysctl(mib, &buf[0], &n, nil, 0); err != nil {
 		return 0, err
 	}
 	if n != 4 {
@@ -498,6 +518,49 @@ func SysctlUint32(name string) (value uint32, err error) {
 	return *(*uint32)(unsafe.Pointer(&buf[0])), nil
 }
 
+func SysctlUint64(name string, args ...int) (uint64, error) {
+	mib, err := sysctlmib(name, args...)
+	if err != nil {
+		return 0, err
+	}
+
+	n := uintptr(8)
+	buf := make([]byte, 8)
+	if err := sysctl(mib, &buf[0], &n, nil, 0); err != nil {
+		return 0, err
+	}
+	if n != 8 {
+		return 0, EIO
+	}
+	return *(*uint64)(unsafe.Pointer(&buf[0])), nil
+}
+
+func SysctlRaw(name string, args ...int) ([]byte, error) {
+	mib, err := sysctlmib(name, args...)
+	if err != nil {
+		return nil, err
+	}
+
+	// Find size.
+	n := uintptr(0)
+	if err := sysctl(mib, nil, &n, nil, 0); err != nil {
+		return nil, err
+	}
+	if n == 0 {
+		return nil, nil
+	}
+
+	// Read into buffer of that size.
+	buf := make([]byte, n)
+	if err := sysctl(mib, &buf[0], &n, nil, 0); err != nil {
+		return nil, err
+	}
+
+	// The actual call may return less than the original reported required
+	// size so ensure we deal with that.
+	return buf[:n], nil
+}
+
 //sys	utimes(path string, timeval *[2]Timeval) (err error)
 
 func Utimes(path string, tv []Timeval) error {
diff --git a/unix/syscall_bsd_test.go b/unix/syscall_bsd_test.go
index 55d88430..0bcd741f 100644
--- a/unix/syscall_bsd_test.go
+++ b/unix/syscall_bsd_test.go
@@ -33,3 +33,10 @@ func TestGetfsstat(t *testing.T) {
 		}
 	}
 }
+
+func TestSysctlRaw(t *testing.T) {
+	_, err := unix.SysctlRaw("kern.proc.pid", unix.Getpid())
+	if err != nil {
+		t.Fatal(err)
+	}
+}
diff --git a/unix/syscall_freebsd_test.go b/unix/syscall_freebsd_test.go
new file mode 100644
index 00000000..6171a017
--- /dev/null
+++ b/unix/syscall_freebsd_test.go
@@ -0,0 +1,20 @@
+// Copyright 2014 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 freebsd
+
+package unix_test
+
+import (
+	"testing"
+
+	"golang.org/x/sys/unix"
+)
+
+func TestSysctUint64(t *testing.T) {
+	_, err := unix.SysctlUint64("vm.max_kernel_address")
+	if err != nil {
+		t.Fatal(err)
+	}
+}