if perr, ok := err.(*PathError); !ok || perr.Err != syscall.ESPIPE {
		t.Errorf("Seek returned error %v, want &PathError{Err: syscall.ESPIPE}", err)
	}
	_, err = w.Seek(0, 0)
	if err == nil {
		t.Fatal("Seek on pipe should fail")
	}
	if perr, ok := err.(*PathError); !ok || perr.Err != syscall.ESPIPE {
		t.Errorf("Seek returned error %v, want &PathError{Err: syscall.ESPIPE}", err)
	}
}

type openErrorTest struct {

	EREMCHG         = Errno(0x52)
	EREMOTE         = Errno(0x42)
	ERESTART        = Errno(0x5b)
	EROFS           = Errno(0x1e)
	ESHUTDOWN       = Errno(0x8f)
	ESOCKTNOSUPPORT = Errno(0x79)
	ESPIPE          = Errno(0x1d)
	ESRCH           = Errno(0x3)
	ESRMNT          = Errno(0x45)
	ESTALE          = Errno(0x97)
	ESTRPIPE        = Errno(0x5c)
	ETIME           = Errno(0x3e)
	ETIMEDOUT       = Errno(0x91)