fdopen-tests: port to Tru64 * tests/test-fdopen.c (main): Don't invoke fdopen on a file descriptors that is not open, as POSIX doesn't specify the resulting behavior and the test does not work on Tru64. Problem reported by Steven M. Schweda in: http://lists.gnu.org/archive/html/bug-gnulib/2014-01/msg00079.html