def testLink(self):
        def _check(results):
            self.flushLoggedErrors()
            self.assertEqual(results[0], '')
            self.assertTrue(results[1].startswith('l'), 'link failed')
            return self.runCommand('rm testLink')

        d = self.runScript('ln testLink testfile1', 'ls -l testLink')
        d.addCallback(_check)
        d.addCallback(self.assertEqual, '')
        return d
Test that 'ln' creates a file which appears as a link in the output of
dataset/ETHPy150Open twisted/twisted/twisted/conch/test/test_cftp.py/OurServerCmdLineClientTests.testLink