diff -r 6297fcddf912 Lib/idlelib/run.py
--- a/Lib/idlelib/run.py	Fri Apr 19 12:57:54 2013 -0400
+++ b/Lib/idlelib/run.py	Sat Apr 27 20:45:34 2013 -0500
@@ -293,6 +293,10 @@
         sys.stderr = PyShell.PseudoOutputFile(self.console, "stderr",
                 IOBinding.encoding)
 
+        # Keep a reference to stdin so that it won't try to exit IDLE
+        # if sys.stdin gets changed from within IDLE's shell. See issue17838.
+        self._keep_stdin = sys.stdin
+
         sys.displayhook = rpc.displayhook
         # page help() text to shell.
         import pydoc # import must be done here to capture i/o binding