Merged revisions 87233 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/branches/py3k
........
r87233 | gregory.p.smith | 2010-12-14 06:38:00 -0800 (Tue, 14 Dec 2010) | 4 lines
Issue #1731717: Fixed the problem where subprocess.wait() could cause an
OSError exception when The OS had been told to ignore SIGCLD in our process
or otherwise not wait for exiting child processes.
........
diff --git a/Lib/subprocess.py b/Lib/subprocess.py
index 24bf321..4c235d9 100644
--- a/Lib/subprocess.py
+++ b/Lib/subprocess.py
@@ -1194,7 +1194,11 @@
os.close(errpipe_read)
if data != "":
- _eintr_retry_call(os.waitpid, self.pid, 0)
+ try:
+ _eintr_retry_call(os.waitpid, self.pid, 0)
+ except OSError as e:
+ if e.errno != errno.ECHILD:
+ raise
child_exception = pickle.loads(data)
for fd in (p2cwrite, c2pread, errread):
if fd is not None:
@@ -1240,7 +1244,15 @@
"""Wait for child process to terminate. Returns returncode
attribute."""
if self.returncode is None:
- pid, sts = _eintr_retry_call(os.waitpid, self.pid, 0)
+ try:
+ pid, sts = _eintr_retry_call(os.waitpid, self.pid, 0)
+ except OSError as e:
+ if e.errno != errno.ECHILD:
+ raise
+ # This happens if SIGCLD is set to be ignored or waiting
+ # for child processes has otherwise been disabled for our
+ # process. This child is dead, we can't get the status.
+ sts = 0
self._handle_exitstatus(sts)
return self.returncode
diff --git a/Lib/test/subprocessdata/sigchild_ignore.py b/Lib/test/subprocessdata/sigchild_ignore.py
new file mode 100644
index 0000000..1d03303
--- /dev/null
+++ b/Lib/test/subprocessdata/sigchild_ignore.py
@@ -0,0 +1,6 @@
+import signal, subprocess, sys
+# On Linux this causes os.waitpid to fail with OSError as the OS has already
+# reaped our child process. The wait() passing the OSError on to the caller
+# and causing us to exit with an error is what we are testing against.
+signal.signal(signal.SIGCLD, signal.SIG_IGN)
+subprocess.Popen([sys.executable, '-c', 'print("albatross")']).wait()
diff --git a/Lib/test/test_subprocess.py b/Lib/test/test_subprocess.py
index 37c4e0f..26adf22 100644
--- a/Lib/test/test_subprocess.py
+++ b/Lib/test/test_subprocess.py
@@ -778,6 +778,16 @@
self.assertStderrEqual(stderr, '')
self.assertEqual(p.wait(), -signal.SIGTERM)
+ def test_wait_when_sigchild_ignored(self):
+ # NOTE: sigchild_ignore.py may not be an effective test on all OSes.
+ sigchild_ignore = test_support.findfile("sigchild_ignore.py",
+ subdir="subprocessdata")
+ p = subprocess.Popen([sys.executable, sigchild_ignore],
+ stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+ stdout, stderr = p.communicate()
+ self.assertEqual(0, p.returncode, "sigchild_ignore.py exited"
+ " non-zero with this error:\n%s" % stderr)
+
@unittest.skipUnless(mswindows, "Windows specific tests")
class Win32ProcessTestCase(BaseTestCase):