diff -r f9f9662dfb1f Lib/test/test_subprocess.py
--- a/Lib/test/test_subprocess.py	Sun Mar 06 01:53:19 2011 +0100
+++ b/Lib/test/test_subprocess.py	Sun Mar 06 16:40:28 2011 -0800
@@ -1217,13 +1217,26 @@
         subprocess.call([sys.executable, "-c", "import sys; sys.exit(0)"],
                         startupinfo=startupinfo)
 
+    def _with_new_console(self, command):
+        # start a subprocess with CREATE_NEW_CONSOLE and the given command
+        CREATE_NEW_CONSOLE = 16
+        sys.stderr.write("    a DOS box should flash briefly ...\n")
+        subprocess.check_call(command, creationflags=CREATE_NEW_CONSOLE)
+
     def test_creationflags(self):
         # creationflags argument
-        CREATE_NEW_CONSOLE = 16
-        sys.stderr.write("    a DOS box should flash briefly ...\n")
-        subprocess.call(sys.executable +
-                        ' -c "import time; time.sleep(0.25)"',
-                        creationflags=CREATE_NEW_CONSOLE)
+        self._with_new_console(sys.executable +
+                               ' -c "import time; time.sleep(0.25)"')
+
+    def test_stdout_large(self):
+        # see: issue #11395
+        self._with_new_console([sys.executable, "-c",
+                                "print(b'a' * 66000)"])
+
+    def test_stdout_binlarge(self):
+        # see: issue #11395
+        self._with_new_console([sys.executable, "-u", "-c",
+                                "print(b'a' * 66000)"])
 
     def test_invalid_args(self):
         # invalid arguments should raise ValueError
diff -r f9f9662dfb1f Modules/_io/fileio.c
--- a/Modules/_io/fileio.c	Sun Mar 06 01:53:19 2011 +0100
+++ b/Modules/_io/fileio.c	Sun Mar 06 16:40:28 2011 -0800
@@ -712,6 +712,12 @@
         errno = 0;
         len = pbuf.len;
 #if defined(MS_WIN64) || defined(MS_WINDOWS)
+#define WIN_CONSOLE_BUFSIZ 32767
+        /* Issue #11395: Resolve "IOError: [Errno 12] Not enough space"
+           when writing into std* in Windows console if the written
+           length is large enough. */
+        if (len > WIN_CONSOLE_BUFSIZ && isatty(self->fd))
+            len = WIN_CONSOLE_BUFSIZ;
         if (len > INT_MAX)
             len = INT_MAX;
         n = write(self->fd, pbuf.buf, (int)len);