diff --git a/io_test.go b/io_test.go
index f68956c..57fbd3d 100644
--- a/io_test.go
+++ b/io_test.go
@@ -1,3 +1,6 @@
+//go:build go1.12
+// +build go1.12
+
 package pty
 
 import (
diff --git a/ioctl.go b/ioctl.go
index 4e26755..60ac9b8 100644
--- a/ioctl.go
+++ b/ioctl.go
@@ -1,7 +1,6 @@
-//go:build !windows
-// +build !windows
+//go:build !windows && go1.12
+// +build !windows,go1.12
 
-//
 package pty
 
 import "os"
diff --git a/ioctl_legacy.go b/ioctl_legacy.go
new file mode 100644
index 0000000..f00b1a1
--- /dev/null
+++ b/ioctl_legacy.go
@@ -0,0 +1,10 @@
+//go:build !windows && !go1.12
+// +build !windows,!go1.12
+
+package pty
+
+import "os"
+
+func ioctl(f *os.File, cmd, ptr uintptr) error {
+	return ioctl_inner(f.Fd(), cmd, ptr) // fall back to blocking io (old behavior)
+}