New modules 'opendir', 'readdir', 'rewinddir', 'closedir'. * lib/dirent.in.h (struct dirent): New type. (DT_UNKNOWN, DT_FIFO, DT_CHR, DT_DIR, DT_BLK, DT_REG, DT_LNK, DT_SOCK, DT_WHT): New macros. (DIR): New type. (opendir, closedir): Declare only if the module 'opendir' is enabled. (readdir, rewinddir): New declarations. * lib/dirent-private.h: New file. * lib/opendir.c: New file. * lib/readdir.c: New file. * lib/rewinddir.c: New file. * lib/closedir.c: New file. * lib/fchdir.c (rpl_closedir, rpl_opendir): Remove functions. * m4/opendir.m4: New file. * m4/readdir.m4: New file. * m4/rewinddir.m4: New file. * m4/closedir.m4: New file. * m4/fchdir.m4 (gl_FUNC_FCHDIR): Don't set REPLACE_OPENDIR, REPLACE_CLOSEDIR here. * m4/dirent_h.m4 (gl_DIRENT_H): Also check whether closedir, opendir, readdir, rewinddir are declared. (gl_DIRENT_H_DEFAULTS): Initialize GNULIB_OPENDIR, GNULIB_READDIR, GNULIB_REWINDDIR, GNULIB_CLOSEDIR, HAVE_OPENDIR, HAVE_READDIR, HAVE_REWINDDIR, HAVE_CLOSEDIR. * modules/dirent (Makefile.am): Substitute GNULIB_OPENDIR, GNULIB_READDIR, GNULIB_REWINDDIR, GNULIB_CLOSEDIR, HAVE_OPENDIR, HAVE_READDIR, HAVE_REWINDDIR, HAVE_CLOSEDIR. * modules/opendir: New file. * modules/readdir: New file. * modules/rewinddir: New file. * modules/closedir: New file. * doc/posix-functions/opendir.texi: Mention the 'opendir' module. * doc/posix-functions/readdir.texi: Mention the 'readdir' module. * doc/posix-functions/rewinddir.texi: Mention the 'rewinddir' module. * doc/posix-functions/closedir.texi: Mention the 'closedir' module. * NEWS: Mention the 'fchdir' change.

# rewinddir.m4 serial 1
dnl Copyright (C) 2011 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.

AC_DEFUN([gl_FUNC_REWINDDIR],
[
  AC_REQUIRE([gl_DIRENT_H_DEFAULTS])

  AC_CHECK_FUNCS([rewinddir])
  if test $ac_cv_func_rewinddir = no; then
    HAVE_REWINDDIR=0
  fi
])