diff -r 760f222103c7 Doc/library/subprocess.rst
--- a/Doc/library/subprocess.rst	Mon Mar 02 09:36:48 2015 -0500
+++ b/Doc/library/subprocess.rst	Tue Mar 03 10:45:00 2015 +0100
@@ -533,9 +533,17 @@ functions.
       with Popen(["ifconfig"], stdout=PIPE) as proc:
           log.write(proc.stdout.read())
 
+   The context manager ignores broken pipe errors when closing the process's
+   stdin: call explicitly ``proc.stdin.flush()`` and ``proc.stdin.close()`` to
+   get broken pipe errors.
+
    .. versionchanged:: 3.2
       Added context manager support.
 
+   .. versionchanged:: 3.5
+      The context manager support now ignores broken pipe errors as
+      the :meth:`~Popen.communicate` method.
+
 
 Exceptions
 ^^^^^^^^^^
@@ -642,6 +650,11 @@ Instances of the :class:`Popen` class ha
    ``None`` in the result tuple, you need to give ``stdout=PIPE`` and/or
    ``stderr=PIPE`` too.
 
+   Broken pipe errors are ignored when sending data to the process's stdin. If
+   the process exits before reading all input data or closes its stdin, the
+   parent gets a broken pipe error. The method ignore this error and so may not
+   send all *input* data.
+
    If the process does not terminate after *timeout* seconds, a
    :exc:`TimeoutExpired` exception will be raised.  Catching this exception and
    retrying communication will not lose any output.
diff -r 760f222103c7 Lib/subprocess.py
--- a/Lib/subprocess.py	Mon Mar 02 09:36:48 2015 -0500
+++ b/Lib/subprocess.py	Tue Mar 03 10:45:00 2015 +0100
@@ -892,12 +892,12 @@ class Popen(object):
             self.stdout.close()
         if self.stderr:
             self.stderr.close()
-        try:  # Flushing a BufferedWriter may raise an error
-            if self.stdin:
-                self.stdin.close()
-        finally:
-            # Wait for the process to terminate, to avoid zombies.
-            self.wait()
+        if self.stdin:
+            # Ignore broken pipe error when closing stdin. stdin is buffered:
+            # close() can flush buffered data and so write data.
+            self._stdin_write(None)
+        # Wait for the process to terminate, to avoid zombies.
+        self.wait()
 
     def __del__(self, _maxsize=sys.maxsize):
         if not self._child_created:
@@ -915,20 +915,22 @@ class Popen(object):
         return self._devnull
 
     def _stdin_write(self, input):
-        if input:
-            try:
+        try:
+            if input:
                 self.stdin.write(input)
-            except BrokenPipeError:
-                # communicate() must ignore broken pipe error
+            # stdin is buffered: close() can flush buffered data and so write
+            # data. We also want to catch errors on close()
+            self.stdin.close()
+        except BrokenPipeError:
+            # communicate() must ignore broken pipe error
+            pass
+        except OSError as e:
+            if e.errno == errno.EINVAL and self.poll() is not None:
+                # Issue #19612: On Windows, stdin.write() fails with EINVAL
+                # if the process already exited before the write
                 pass
-            except OSError as e:
-                if e.errno == errno.EINVAL and self.poll() is not None:
-                    # Issue #19612: On Windows, stdin.write() fails with EINVAL
-                    # if the process already exited before the write
-                    pass
-                else:
-                    raise
-        self.stdin.close()
+            else:
+                raise
 
     def communicate(self, input=None, timeout=None):
         """Interact with process: Send data to stdin.  Read data from