2 files changed, 71 insertions, 2 deletions
diff --git a/Lib/multiprocessing/process.py b/Lib/multiprocessing/process.py
index 4a06a45..1a5c25f 100644
--- a/Lib/multiprocessing/process.py
+++ b/Lib/multiprocessing/process.py
@@ -221,7 +221,8 @@ class Process(object):
             self._counter = itertools.count(1)
             if sys.stdin is not None:
                 try:
-                    os.close(sys.stdin.fileno())
+                    sys.stdin.close()
+                    sys.stdin = open(os.devnull)
                 except (OSError, ValueError):
                     pass
             _current_process = self
diff --git a/Lib/test/test_multiprocessing.py b/Lib/test/test_multiprocessing.py
index 9d58cdc..9f4e1a2 100644
--- a/Lib/test/test_multiprocessing.py
+++ b/Lib/test/test_multiprocessing.py
@@ -8,6 +8,7 @@ import unittest
 import threading
 import queue as pyqueue
 import time
+import io
 import sys
 import os
 import gc
@@ -1862,7 +1863,74 @@ class TestInitializers(unittest.TestCase):
         p.join()
         self.assertEqual(self.ns.test, 1)
 
-testcases_other = [OtherTest, TestInvalidHandle, TestInitializers]
+#
+# Issue 5155, 5313, 5331: Test process in processes
+# Verifies os.close(sys.stdin.fileno) vs. sys.stdin.close() behavior
+#
+
+def _ThisSubProcess(q):
+    try:
+        item = q.get(block=False)
+    except pyqueue.Empty:
+        pass
+
+def _TestProcess(q):
+    queue = multiprocessing.Queue()
+    subProc = multiprocessing.Process(target=_ThisSubProcess, args=(queue,))
+    subProc.start()
+    subProc.join()
+
+def _afunc(x):
+    return x*x
+
+def pool_in_process():
+    pool = multiprocessing.Pool(processes=4)
+    x = pool.map(_afunc, [1, 2, 3, 4, 5, 6, 7])
+
+class _file_like(object):
+    def __init__(self, delegate):
+        self._delegate = delegate
+        self._pid = None
+
+    @property
+    def cache(self):
+        pid = os.getpid()
+        # There are no race conditions since fork keeps only the running thread
+        if pid != self._pid:
+            self._pid = pid
+            self._cache = []
+        return self._cache
+
+    def write(self, data):
+        self.cache.append(data)
+
+    def flush(self):
+        self._delegate.write(''.join(self.cache))
+        self._cache = []
+
+class TestStdinBadfiledescriptor(unittest.TestCase):
+
+    def test_queue_in_process(self):
+        queue = multiprocessing.Queue()
+        proc = multiprocessing.Process(target=_TestProcess, args=(queue,))
+        proc.start()
+        proc.join()
+
+    def test_pool_in_process(self):
+        p = multiprocessing.Process(target=pool_in_process)
+        p.start()
+        p.join()
+
+    def test_flushing(self):
+        sio = io.StringIO()
+        flike = _file_like(sio)
+        flike.write('foo')
+        proc = multiprocessing.Process(target=lambda: flike.flush())
+        flike.flush()
+        assert sio.getvalue() == 'foo'
+
+testcases_other = [OtherTest, TestInvalidHandle, TestInitializers,
+                   TestStdinBadfiledescriptor]
 
 #
 #