/* Retrieve information about a FILE stream.
- Copyright (C) 2007-2011 Free Software Foundation, Inc.
+ Copyright (C) 2007-2021 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
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/>. */
+ along with this program. If not, see <https://www.gnu.org/licenses/>. */
#include <stddef.h>
#include <stdio.h>
-#ifdef __cplusplus
-extern "C" {
-#endif
-
/* Assuming the stream STREAM is open for reading:
Return the number of bytes waiting in the input buffer of STREAM.
This includes both the bytes that have been read from the underlying input
STREAM must not be wide-character oriented. */
-extern size_t freadahead (FILE *stream);
+#if HAVE___FREADAHEAD /* musl libc */
+
+# include <stdio_ext.h>
+# define freadahead(stream) __freadahead (stream)
+
+#else
-#ifdef __cplusplus
+# ifdef __cplusplus
+extern "C" {
+# endif
+
+extern size_t freadahead (FILE *stream) _GL_ATTRIBUTE_PURE;
+
+# ifdef __cplusplus
}
+# endif
+
#endif