diff -r d3f0f72c31f8 Modules/_io/fileio.c
--- a/Modules/_io/fileio.c	Fri Jul 22 11:10:43 2011 -0500
+++ b/Modules/_io/fileio.c	Fri Jul 22 22:33:54 2011 +0200
@@ -823,7 +823,7 @@
         Py_END_ALLOW_THREADS
     } else
         res = -1;
-    if (res < 0)
+    if (res == -1)
         return PyErr_SetFromErrno(PyExc_IOError);
 
 #if defined(HAVE_LARGEFILE_SUPPORT)
diff -r d3f0f72c31f8 Modules/posixmodule.c
--- a/Modules/posixmodule.c	Fri Jul 22 11:10:43 2011 -0500
+++ b/Modules/posixmodule.c	Fri Jul 22 22:33:54 2011 +0200
@@ -6257,7 +6257,7 @@
     res = lseek(fd, pos, how);
 #endif
     Py_END_ALLOW_THREADS
-    if (res < 0)
+    if (res == -1)
         return posix_error();
 
 #if !defined(HAVE_LARGEFILE_SUPPORT)