diff -r d64bb25cf797 Doc/library/multiprocessing.rst
--- a/Doc/library/multiprocessing.rst	Wed Nov 18 02:45:51 2015 +0000
+++ b/Doc/library/multiprocessing.rst	Thu Nov 19 12:16:19 2015 +0200
@@ -2670,7 +2670,7 @@ Beware of replacing :data:`sys.stdin` wi
     in issues with processes-in-processes. This has been changed to::
 
         sys.stdin.close()
-        sys.stdin = open(os.devnull)
+        sys.stdin = open(os.open(os.devnull, os.O_RDONLY), closefd=False)
 
     Which solves the fundamental issue of processes colliding with each other
     resulting in a bad file descriptor error, but introduces a potential danger
diff -r d64bb25cf797 Lib/multiprocessing/forkserver.py
--- a/Lib/multiprocessing/forkserver.py	Wed Nov 18 02:45:51 2015 +0000
+++ b/Lib/multiprocessing/forkserver.py	Thu Nov 19 12:16:19 2015 +0200
@@ -147,13 +147,7 @@ def main(listener_fd, alive_r, preload, 
             except ImportError:
                 pass
 
-    # close sys.stdin
-    if sys.stdin is not None:
-        try:
-            sys.stdin.close()
-            sys.stdin = open(os.devnull)
-        except (OSError, ValueError):
-            pass
+    util._close_stdin()
 
     # ignoring SIGCHLD means no need to reap zombie processes
     handler = signal.signal(signal.SIGCHLD, signal.SIG_IGN)
diff -r d64bb25cf797 Lib/multiprocessing/process.py
--- a/Lib/multiprocessing/process.py	Wed Nov 18 02:45:51 2015 +0000
+++ b/Lib/multiprocessing/process.py	Thu Nov 19 12:16:19 2015 +0200
@@ -234,12 +234,7 @@ class BaseProcess(object):
                 context._force_start_method(self._start_method)
             _process_counter = itertools.count(1)
             _children = set()
-            if sys.stdin is not None:
-                try:
-                    sys.stdin.close()
-                    sys.stdin = open(os.devnull)
-                except (OSError, ValueError):
-                    pass
+            util._close_stdin()
             old_process = _current_process
             _current_process = self
             try:
diff -r d64bb25cf797 Lib/multiprocessing/util.py
--- a/Lib/multiprocessing/util.py	Wed Nov 18 02:45:51 2015 +0000
+++ b/Lib/multiprocessing/util.py	Thu Nov 19 12:16:19 2015 +0200
@@ -9,6 +9,7 @@
 
 import os
 import itertools
+import sys
 import weakref
 import atexit
 import threading        # we want threading to install it's
@@ -356,6 +357,22 @@ def close_all_fds_except(fds):
     assert fds[-1] == MAXFD, 'fd too large'
     for i in range(len(fds) - 1):
         os.closerange(fds[i]+1, fds[i+1])
+#
+# Close sys.stdin
+#
+
+def _close_stdin():
+    if sys.stdin is not None:
+        try:
+            sys.stdin.close()
+            fd = os.open(os.devnull, os.O_RDONLY)
+            try:
+                sys.stdin = open(fd, closefd=False)
+            except:
+                os.close(fd)
+                raise
+        except (OSError, ValueError):
+            pass
 
 #
 # Start a program with only specified fds kept open
diff -r d64bb25cf797 Lib/test/_test_multiprocessing.py
--- a/Lib/test/_test_multiprocessing.py	Wed Nov 18 02:45:51 2015 +0000
+++ b/Lib/test/_test_multiprocessing.py	Thu Nov 19 12:16:19 2015 +0200
@@ -455,13 +455,17 @@ class _TestSubclassingProcess(BaseTestCa
 
     @classmethod
     def _test_stderr_flush(cls, testfn):
-        sys.stderr = open(testfn, 'w')
+        if not isinstance(testfn, int):
+            testfn = os.open(testfn, os.O_RDWR|os.O_CREAT)
+        sys.stderr = open(testfn, 'w', closefd=False)
         1/0 # MARKER
 
 
     @classmethod
     def _test_sys_exit(cls, reason, testfn):
-        sys.stderr = open(testfn, 'w')
+        if not isinstance(testfn, int):
+            testfn = os.open(testfn, os.O_RDWR|os.O_CREAT)
+        sys.stderr = open(testfn, 'w', closefd=False)
         sys.exit(reason)
 
     def test_sys_exit(self):