diff --git a/Lib/asyncore.py b/Lib/asyncore.py
index f790c8a0183..d6476069be0 100644
--- a/Lib/asyncore.py
+++ b/Lib/asyncore.py
@@ -54,7 +54,8 @@ import warnings
 
 import os
 from errno import EALREADY, EINPROGRESS, EWOULDBLOCK, ECONNRESET, EINVAL, \
-     ENOTCONN, ESHUTDOWN, EINTR, EISCONN, EBADF, ECONNABORTED, EPIPE, errorcode
+     ENOTCONN, ESHUTDOWN, EINTR, EISCONN, EBADF, ECONNABORTED, EPIPE, EAGAIN, \
+     errorcode
 
 _DISCONNECTED = frozenset((ECONNRESET, ENOTCONN, ESHUTDOWN, ECONNABORTED, EPIPE,
                            EBADF))