fts: close parent dir FD before returning from post-traversal fts_read The problem: the fts-using "mkdir -p A/B; rm -rf A" would attempt to unlink A, even though an FD open on A remained. This is suboptimal (holding a file descriptor open longer than needed), but otherwise not a problem on Unix-like kernels. However, on Cygwin with certain Novell file systems, (see http://cygwin.com/ml/cygwin/2011-10/msg00365.html), that represents a real problem: it causes the removal of A to fail with e.g., "rm: cannot remove `A': Device or resource busy" fts visits each directory twice and keeps a cache (fts_fd_ring) of directory file descriptors. After completing the final, FTS_DP, visit of a directory, RESTORE_INITIAL_CWD intended to clear the FD cache, but then proceeded to add a new FD to it via the subsequent FCHDIR (which calls cwd_advance_fd and i_ring_push). Before, the final file descriptor would be closed only via fts_close's call to fd_ring_clear. Now, it is usually closed earlier, via the final FTS_DP-returning fts_read call. * lib/fts.c (restore_initial_cwd): New function, converted from the macro. Call fd_ring_clear *after* FCHDIR, not before it. Update callers. Reported by Franz Sirl via the above URL, with analysis by Eric Blake in http://thread.gmane.org/gmane.comp.lib.gnulib.bugs/28739

/* Substitute for and wrapper around <stdarg.h>.
   Copyright (C) 2008-2011 Free Software Foundation, Inc.

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#ifndef _@GUARD_PREFIX@_STDARG_H

#if __GNUC__ >= 3
@PRAGMA_SYSTEM_HEADER@
#endif
@PRAGMA_COLUMNS@

/* The include_next requires a split double-inclusion guard.  */
#@INCLUDE_NEXT@ @NEXT_STDARG_H@

#ifndef _@GUARD_PREFIX@_STDARG_H
#define _@GUARD_PREFIX@_STDARG_H

#ifndef va_copy
# define va_copy(a,b) ((a) = (b))
#endif

#endif /* _@GUARD_PREFIX@_STDARG_H */
#endif /* _@GUARD_PREFIX@_STDARG_H */