Rename reentrant.m4 to avoid filename clash.

m4/cares-reentrant.m4

@@ -1,6 +1,28 @@
-
-
-# serial 1.10
+#***************************************************************************
+# $Id$
+#
+# Copyright (C) 2008 by Daniel Stenberg et al
+#
+# Permission to use, copy, modify, and distribute this software and its
+# documentation for any purpose and without fee is hereby granted, provided
+# that the above copyright notice appear in all copies and that both that
+# copyright notice and this permission notice appear in supporting
+# documentation, and that the name of M.I.T. not be used in advertising or
+# publicity pertaining to distribution of the software without specific,
+# written prior permission.  M.I.T. makes no representations about the
+# suitability of this software for any purpose.  It is provided "as is"
+# without express or implied warranty.
+#
+#***************************************************************************
+
+# File version for 'aclocal' use.
+# serial 1.1
+
+dnl Note 1
+dnl ------
+dnl None of the CARES_CHECK_NEED_REENTRANT_* macros shall use HAVE_FOO_H to
+dnl conditionally include header files. These macros are used early in the
+dnl configure process much before header file availability is known.
 
 
 dnl CARES_CHECK_NEED_REENTRANT_GMTIME_R
@@ -354,13 +376,13 @@ dnl and that in turn setup.h will define _REENTRANT.
 dnl Internal macro for CARES_CONFIGURE_REENTRANT.
 
 AC_DEFUN([CARES_CONFIGURE_FROM_NOW_ON_WITH_REENTRANT], [
-AC_DEFINE([NEED_REENTRANT], [1],
+AC_DEFINE(NEED_REENTRANT, 1,
   [Define to 1 if _REENTRANT preprocessor symbol must be defined.])
-cat >>confdefs.h <<_ACEOF
+cat >>confdefs.h <<_EOF
 #ifndef _REENTRANT
-#define _REENTRANT
+#  define _REENTRANT
 #endif
-_ACEOF
+_EOF
 ])