+ dnl Work around a bug of AC_EGREP_CPP in autoconf-2.57.
+ AC_REQUIRE([AC_PROG_CPP])
+ AC_REQUIRE([AC_PROG_EGREP])
+
+ AC_HEADER_DIRENT
+ dirfd_headers='
+#if HAVE_DIRENT_H
+# include <dirent.h>
+#else /* not HAVE_DIRENT_H */
+# define dirent direct
+# if HAVE_SYS_NDIR_H
+# include <sys/ndir.h>
+# endif /* HAVE_SYS_NDIR_H */
+# if HAVE_SYS_DIR_H
+# include <sys/dir.h>
+# endif /* HAVE_SYS_DIR_H */
+# if HAVE_NDIR_H
+# include <ndir.h>
+# endif /* HAVE_NDIR_H */
+#endif /* HAVE_DIRENT_H */
+'
+ AC_CHECK_FUNCS(dirfd)
+ AC_CHECK_DECLS([dirfd], , , $dirfd_headers)
+
+ AC_CACHE_CHECK([whether dirfd is a macro],
+ jm_cv_func_dirfd_macro,
+ AC_EGREP_CPP([dirent_header_defines_dirfd], [$dirfd_headers
+#ifdef dirfd
+ dirent_header_defines_dirfd
+#endif],
+ jm_cv_func_dirfd_macro=yes,
+ jm_cv_func_dirfd_macro=no))
+
+ # Use the replacement only if we have no function, macro,
+ # or declaration with that name.
+ if test $ac_cv_func_dirfd,$ac_cv_have_decl_dirfd,$jm_cv_func_dirfd_macro \
+ = no,no,no; then
+ AC_REPLACE_FUNCS([dirfd])