From 74fa9f723f700a342e582b5ad4b51a2c4801cd1c Mon Sep 17 00:00:00 2001 From: Benjamin Peterson Date: Tue, 12 Nov 2019 14:51:34 -0800 Subject: closes bpo-27805: Ignore ESPIPE in initializing seek of append-mode files. (GH-17112) This change, which follows the behavior of C stdio's fdopen and Python 2's file object, allows pipes to be opened in append mode. --- Lib/test/test_io.py | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'Lib/test/test_io.py') diff --git a/Lib/test/test_io.py b/Lib/test/test_io.py index ad22dfe9b2..501e931396 100644 --- a/Lib/test/test_io.py +++ b/Lib/test/test_io.py @@ -3906,6 +3906,17 @@ class MiscIOTest(unittest.TestCase): self.open(support.TESTFN, mode) self.assertIn('invalid mode', str(cm.exception)) + def test_open_pipe_with_append(self): + # bpo-27805: Ignore ESPIPE from lseek() in open(). + r, w = os.pipe() + self.addCleanup(os.close, r) + f = self.open(w, 'a') + self.addCleanup(f.close) + # Check that the file is marked non-seekable. On Windows, however, lseek + # somehow succeeds on pipes. + if sys.platform != 'win32': + self.assertFalse(f.seekable()) + def test_io_after_close(self): for kwargs in [ {"mode": "w"}, -- cgit v1.2.1