Merged revisions 70690,70692 via svnmerge from

Merged revisions 70690,70692 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/branches/py3k

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  r70690 | antoine.pitrou | 2009-03-29 20:40:13 +0200 (dim., 29 mars 2009) | 3 lines

  Fix leak in _fileio.c (patch by Hirokazu Yamamoto)
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  r70692 | antoine.pitrou | 2009-03-29 20:55:12 +0200 (dim., 29 mars 2009) | 4 lines

  Plug another leak, and finally add a test for #1174606 (read() from /dev/zero).
  The leak was the reason my previous attempts at testing failed...
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