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cffi / c / file_emulator.h

The branch 'release-0.4' does not exist.
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c/file_emulator.h

             PyErr_SetFromErrno(PyExc_OSError);
             goto fail;
         }
+        setbuf(f, NULL);    /* non-buffered */
         Py_DECREF(ob_mode);
         ob_mode = NULL;