Merged revisions 78835-78837 via svnmerge from

Merged revisions 78835-78837 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk

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  r78835 | victor.stinner | 2010-03-11 13:34:39 +0100 (jeu., 11 mars 2010) | 7 lines

  Issue #7774: Set sys.executable to an empty string if argv[0] has been
  set to an non existent program name and Python is unable to retrieve the real
  program name.

  Fix also sysconfig: if sys.executable is an empty string, use the current
  working directory.
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  r78836 | victor.stinner | 2010-03-11 14:27:35 +0100 (jeu., 11 mars 2010) | 4 lines

  Fix test_executable introduce in previous commit (r78835): Windows is able to
  retrieve the absolute Python path even if argv[0] has been set to a non
  existent program name.
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  r78837 | victor.stinner | 2010-03-11 14:46:06 +0100 (jeu., 11 mars 2010) | 3 lines

  Another fix to test_executable() of test_sys: set the current working to avoid
  the #7774 bug.
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