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+/* areadlinkat.c -- readlinkat wrapper to return malloc'd link name
+ Unlike xreadlinkat, only call exit on failure to change directory.
+
+ Copyright (C) 2001, 2003-2007, 2009-2015 Free Software Foundation, Inc.
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
+
+/* Written by Jim Meyering <jim@meyering.net>,
+ and Bruno Haible <bruno@clisp.org>,
+ and Eric Blake <ebb9@byu.net>. */
+
+#include <config.h>
+
+/* Specification. */
+#include "areadlink.h"
+
+#include "careadlinkat.h"
+
+#if HAVE_READLINKAT
+
+/* Call readlinkat to get the symbolic link value of FILENAME relative to FD.
+ Return a pointer to that NUL-terminated string in malloc'd storage.
+ If readlinkat fails, return NULL and set errno (although failure to
+ change directory will issue a diagnostic and exit).
+ If allocation fails, or if the link value is longer than SIZE_MAX :-),
+ return NULL and set errno to ENOMEM. */
+
+char *
+areadlinkat (int fd, char const *filename)
+{
+ return careadlinkat (fd, filename, NULL, 0, NULL, readlinkat);
+}
+
+#else /* !HAVE_READLINKAT */
+
+/* It is more efficient to change directories only once and call
+ areadlink, rather than repeatedly call the replacement
+ readlinkat. */
+
+# define AT_FUNC_NAME areadlinkat
+# define AT_FUNC_F1 areadlink
+# define AT_FUNC_POST_FILE_PARAM_DECLS /* empty */
+# define AT_FUNC_POST_FILE_ARGS /* empty */
+# define AT_FUNC_RESULT char *
+# define AT_FUNC_FAIL NULL
+# include "at-func.c"
+# undef AT_FUNC_NAME
+# undef AT_FUNC_F1
+# undef AT_FUNC_POST_FILE_PARAM_DECLS
+# undef AT_FUNC_POST_FILE_ARGS
+# undef AT_FUNC_RESULT
+# undef AT_FUNC_FAIL
+
+#endif /* !HAVE_READLINKAT */