diff --git a/.travis.yml b/.travis.yml
index 183f1b7d..0cbcbcb2 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -4,10 +4,9 @@ script:
   - go test -race -v ./...
 
 go:
-  - 1.5
-  - 1.6
   - 1.7
   - 1.8
+  - 1.9
   - tip
 
 matrix:
diff --git a/cmd/gotail/gotail.go b/cmd/gotail/gotail.go
index 3da55f23..3c769447 100644
--- a/cmd/gotail/gotail.go
+++ b/cmd/gotail/gotail.go
@@ -6,6 +6,7 @@ package main
 import (
 	"flag"
 	"fmt"
+	"io"
 	"os"
 
 	"github.com/hpcloud/tail"
@@ -36,7 +37,7 @@ func main() {
 	}
 
 	if n != 0 {
-		config.Location = &tail.SeekInfo{-n, os.SEEK_END}
+		config.Location = &tail.SeekInfo{-n, io.SeekEnd}
 	}
 
 	done := make(chan bool)
diff --git a/tail.go b/tail.go
index c99cdaa2..9dd069ff 100644
--- a/tail.go
+++ b/tail.go
@@ -36,10 +36,10 @@ func NewLine(text string) *Line {
 	return &Line{text, time.Now(), nil}
 }
 
-// SeekInfo represents arguments to `os.Seek`
+// SeekInfo represents arguments to `io.Seek`
 type SeekInfo struct {
 	Offset int64
-	Whence int // os.SEEK_*
+	Whence int // io.Seek*
 }
 
 type logger interface {
@@ -143,7 +143,7 @@ func (tail *Tail) Tell() (offset int64, err error) {
 	if tail.file == nil {
 		return
 	}
-	offset, err = tail.file.Seek(0, os.SEEK_CUR)
+	offset, err = tail.file.Seek(0, io.SeekCurrent)
 	if err != nil {
 		return
 	}
@@ -336,7 +336,7 @@ func (tail *Tail) tailFileSync() {
 // reopened if ReOpen is true. Truncated files are always reopened.
 func (tail *Tail) waitForChanges() error {
 	if tail.changes == nil {
-		pos, err := tail.file.Seek(0, os.SEEK_CUR)
+		pos, err := tail.file.Seek(0, io.SeekCurrent)
 		if err != nil {
 			return err
 		}
@@ -389,7 +389,7 @@ func (tail *Tail) openReader() {
 }
 
 func (tail *Tail) seekEnd() error {
-	return tail.seekTo(SeekInfo{Offset: 0, Whence: os.SEEK_END})
+	return tail.seekTo(SeekInfo{Offset: 0, Whence: io.SeekEnd})
 }
 
 func (tail *Tail) seekTo(pos SeekInfo) error {
diff --git a/tail_test.go b/tail_test.go
index 38d6b84b..975579ab 100644
--- a/tail_test.go
+++ b/tail_test.go
@@ -8,6 +8,7 @@ package tail
 
 import (
 	_ "fmt"
+	"io"
 	"io/ioutil"
 	"os"
 	"strings"
@@ -178,7 +179,7 @@ func TestLocationFullDontFollow(t *testing.T) {
 func TestLocationEnd(t *testing.T) {
 	tailTest := NewTailTest("location-end", t)
 	tailTest.CreateFile("test.txt", "hello\nworld\n")
-	tail := tailTest.StartTail("test.txt", Config{Follow: true, Location: &SeekInfo{0, os.SEEK_END}})
+	tail := tailTest.StartTail("test.txt", Config{Follow: true, Location: &SeekInfo{0, io.SeekEnd}})
 	go tailTest.VerifyTailOutput(tail, []string{"more", "data"}, false)
 
 	<-time.After(100 * time.Millisecond)
@@ -195,7 +196,7 @@ func TestLocationMiddle(t *testing.T) {
 	// Test reading from middle.
 	tailTest := NewTailTest("location-middle", t)
 	tailTest.CreateFile("test.txt", "hello\nworld\n")
-	tail := tailTest.StartTail("test.txt", Config{Follow: true, Location: &SeekInfo{-6, os.SEEK_END}})
+	tail := tailTest.StartTail("test.txt", Config{Follow: true, Location: &SeekInfo{-6, io.SeekEnd}})
 	go tailTest.VerifyTailOutput(tail, []string{"world", "more", "data"}, false)
 
 	<-time.After(100 * time.Millisecond)
@@ -263,7 +264,7 @@ func TestTell(t *testing.T) {
 	tailTest.CreateFile("test.txt", "hello\nworld\nagain\nmore\n")
 	config := Config{
 		Follow:   false,
-		Location: &SeekInfo{0, os.SEEK_SET}}
+		Location: &SeekInfo{0, io.SeekStart}}
 	tail := tailTest.StartTail("test.txt", config)
 	// read noe line
 	<-tail.Lines
@@ -276,7 +277,7 @@ func TestTell(t *testing.T) {
 
 	config = Config{
 		Follow:   false,
-		Location: &SeekInfo{offset, os.SEEK_SET}}
+		Location: &SeekInfo{offset, io.SeekStart}}
 	tail = tailTest.StartTail("test.txt", config)
 	for l := range tail.Lines {
 		// it may readed one line in the chan(tail.Lines),