diff -urp A/Modules/_io/bufferedio.c B/Modules/_io/bufferedio.c
--- A/Modules/_io/bufferedio.c	2010-12-21 22:26:09.000000000 +0100
+++ B/Modules/_io/bufferedio.c	2011-01-09 18:46:01.000000000 +0100
@@ -1405,6 +1405,10 @@ _bufferedreader_read_generic(buffered *s
         }
         remaining -= r;
         written += r;
+        /* check pending signals */
+        if (PyErr_CheckSignals() < 0) {
+            goto error;
+        }
     }
     assert(remaining <= self->buffer_size);
     self->pos = 0;
@@ -1442,6 +1446,10 @@ _bufferedreader_read_generic(buffered *s
         }
         if (remaining == 0)
             break;
+        /* check pending signals */
+        if (PyErr_CheckSignals() < 0) {
+            goto error;
+        }
     }
 
     return res;
diff -urp A/Modules/_io/fileio.c B/Modules/_io/fileio.c
--- A/Modules/_io/fileio.c	2010-11-26 09:52:36.000000000 +0100
+++ B/Modules/_io/fileio.c	2011-01-09 19:26:52.000000000 +0100
@@ -583,6 +583,11 @@ fileio_readall(fileio *self)
             return NULL;
         }
         total += n;
+        /* check pending signals */
+        if (PyErr_CheckSignals() < 0) {
+            Py_DECREF(result);
+            return NULL;
+        }
     }
 
     if (PyBytes_GET_SIZE(result) > total) {
diff -urp A/Modules/_io/iobase.c B/Modules/_io/iobase.c
--- A/Modules/_io/iobase.c	2010-09-14 20:53:07.000000000 +0200
+++ B/Modules/_io/iobase.c	2011-01-09 19:27:15.000000000 +0100
@@ -831,6 +831,11 @@ rawiobase_readall(PyObject *self, PyObje
             Py_DECREF(chunks);
             return NULL;
         }
+        /* check pending signals */
+        if (PyErr_CheckSignals() < 0) {
+            Py_DECREF(chunks);
+            return NULL;
+        }
     }
     result = _PyBytes_Join(_PyIO_empty_bytes, chunks);
     Py_DECREF(chunks);