+AC_PATH_PROG([M4], [m4 gm4], [no])
+if test "x$M4" = xno ; then
+ AC_MSG_ERROR([m4 missing])
+fi
+
+AC_MSG_CHECKING([for tcpwrap library and headers])
+LIBWRAP_LIBS=
+saved_LIBS="$LIBS"
+LIBS="$LIBS -lwrap"
+AC_LINK_IFELSE(
+AC_LANG_PROGRAM(
+[#include <tcpd.h>
+#include <syslog.h>
+int allow_severity = LOG_INFO;
+int deny_severity = LOG_WARNING;],
+[struct request_info *req;
+return hosts_access (req);]),
+[AC_DEFINE(HAVE_LIBWRAP, [], [Have tcpwrap?])
+LIBWRAP_LIBS="-lwrap"
+AC_MSG_RESULT(yes)],
+[AC_MSG_RESULT(no)])
+AC_SUBST(LIBWRAP_LIBS)
+LIBS="$saved_LIBS"
+
+# If using GCC specify some additional parameters