to define an interface called <code>Locker</code>:
</p>

<pre>
type Locker interface {
	Lock()
	Unlock()
}
</pre>

<p>
If <code>S1</code> and <code>S2</code> also implement
</p>

<pre>
func (p T) Lock() { … }
func (p T) Unlock() { … }
</pre>

<p>
they implement the <code>Locker</code> interface as well
as the <code>File</code> interface.

pkg syscall (darwin-arm64), func Setuid(int) error
pkg syscall (darwin-arm64), func Shutdown(int, int) error
pkg syscall (darwin-arm64), func SlicePtrFromStrings([]string) ([]*uint8, error)
pkg syscall (darwin-arm64), func Socket(int, int, int) (int, error)
pkg syscall (darwin-arm64), func Socketpair(int, int, int) ([2]int, error)
pkg syscall (darwin-arm64), func Stat(string, *Stat_t) error

pkg syscall (netbsd-arm64-cgo), func Shutdown(int, int) error
pkg syscall (netbsd-arm64-cgo), func SlicePtrFromStrings([]string) ([]*uint8, error)
pkg syscall (netbsd-arm64-cgo), func Socket(int, int, int) (int, error)
pkg syscall (netbsd-arm64-cgo), func Socketpair(int, int, int) ([2]int, error)
pkg syscall (netbsd-arm64-cgo), func Stat(string, *Stat_t) error