diff --git a/vendor/golang.org/x/sys/unix/ioctl_zos.go b/vendor/golang.org/x/sys/unix/ioctl_zos.go
new file mode 100644
index 0000000..5384e7d
--- /dev/null
+++ b/vendor/golang.org/x/sys/unix/ioctl_zos.go
@@ -0,0 +1,74 @@
+// Copyright 2020 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.
+
+//go:build zos && s390x
+// +build zos,s390x
+
+package unix
+
+import (
+	"runtime"
+	"unsafe"
+)
+
+// ioctl itself should not be exposed directly, but additional get/set
+// functions for specific types are permissible.
+
+// IoctlSetInt performs an ioctl operation which sets an integer value
+// on fd, using the specified request number.
+func IoctlSetInt(fd int, req uint, value int) error {
+	return ioctl(fd, req, uintptr(value))
+}
+
+// IoctlSetWinsize performs an ioctl on fd with a *Winsize argument.
+//
+// To change fd's window size, the req argument should be TIOCSWINSZ.
+func IoctlSetWinsize(fd int, req uint, value *Winsize) error {
+	// TODO: if we get the chance, remove the req parameter and
+	// hardcode TIOCSWINSZ.
+	err := ioctl(fd, req, uintptr(unsafe.Pointer(value)))
+	runtime.KeepAlive(value)
+	return err
+}
+
+// IoctlSetTermios performs an ioctl on fd with a *Termios.
+//
+// The req value is expected to be TCSETS, TCSETSW, or TCSETSF
+func IoctlSetTermios(fd int, req uint, value *Termios) error {
+	if (req != TCSETS) && (req != TCSETSW) && (req != TCSETSF) {
+		return ENOSYS
+	}
+	err := Tcsetattr(fd, int(req), value)
+	runtime.KeepAlive(value)
+	return err
+}
+
+// IoctlGetInt performs an ioctl operation which gets an integer value
+// from fd, using the specified request number.
+//
+// A few ioctl requests use the return value as an output parameter;
+// for those, IoctlRetInt should be used instead of this function.
+func IoctlGetInt(fd int, req uint) (int, error) {
+	var value int
+	err := ioctl(fd, req, uintptr(unsafe.Pointer(&value)))
+	return value, err
+}
+
+func IoctlGetWinsize(fd int, req uint) (*Winsize, error) {
+	var value Winsize
+	err := ioctl(fd, req, uintptr(unsafe.Pointer(&value)))
+	return &value, err
+}
+
+// IoctlGetTermios performs an ioctl on fd with a *Termios.
+//
+// The req value is expected to be TCGETS
+func IoctlGetTermios(fd int, req uint) (*Termios, error) {
+	var value Termios
+	if req != TCGETS {
+		return &value, ENOSYS
+	}
+	err := Tcgetattr(fd, &value)
+	return &value, err
+}