Paul Jakma:

lib/debug.{c,h}: glibc backtrace printing function (from the glibc info page)
configure.ac: check for glibc backtrace and set define
lib/zebra.h: glibc backtrace support
diff --git a/lib/debug.h b/lib/debug.h
new file mode 100644
index 0000000..4440904
--- /dev/null
+++ b/lib/debug.h
@@ -0,0 +1,3 @@
+
+void debug_print_trace (int);
+