diff --git a/nfs/rpc/client.go b/nfs/rpc/client.go
index c70e5e1..2288125 100644
--- a/nfs/rpc/client.go
+++ b/nfs/rpc/client.go
@@ -10,10 +10,8 @@ import (
 	"io"
 	"math/rand"
 	"net"
-	"os"
 	"sync"
 	"sync/atomic"
-	"syscall"
 	"time"
 
 	"github.com/willscott/go-nfs-client/nfs/util"
@@ -58,15 +56,6 @@ type Client struct {
 	replies map[uint32]chan io.ReadSeeker
 }
 
-func isAddrInUse(err error) bool {
-	if er, ok := (err.(*net.OpError)); ok {
-		if syser, ok := er.Err.(*os.SyscallError); ok {
-			return syser.Err == syscall.EADDRINUSE
-		}
-	}
-	return false
-}
-
 func DialTCP(network string, addr string, privileged bool) (*Client, error) {
 	c := &Client{
 		network:    network,
diff --git a/nfs/rpc/client_plan9.go b/nfs/rpc/client_plan9.go
new file mode 100644
index 0000000..1f86134
--- /dev/null
+++ b/nfs/rpc/client_plan9.go
@@ -0,0 +1,10 @@
+// Copyright © 2017 VMware, Inc. All Rights Reserved.
+// SPDX-License-Identifier: BSD-2-Clause
+package rpc
+
+func isAddrInUse(err error) bool {
+	if err != nil && err.Error() == "address in use" {
+		return true
+	}
+	return false
+}
diff --git a/nfs/rpc/client_unix.go b/nfs/rpc/client_unix.go
new file mode 100644
index 0000000..4b1860c
--- /dev/null
+++ b/nfs/rpc/client_unix.go
@@ -0,0 +1,20 @@
+//go:build darwin || dragonfly || freebsd || linux || nacl || netbsd || openbsd || solaris
+
+// Copyright © 2017 VMware, Inc. All Rights Reserved.
+// SPDX-License-Identifier: BSD-2-Clause
+package rpc
+
+import (
+	"net"
+	"os"
+	"syscall"
+)
+
+func isAddrInUse(err error) bool {
+	if er, ok := (err.(*net.OpError)); ok {
+		if syser, ok := er.Err.(*os.SyscallError); ok {
+			return syser.Err == syscall.EADDRINUSE
+		}
+	}
+	return false
+}