+/** \ingroup TRACE_user_variables
+ * \brief Add a value to the variable present in the links connecting source and destination.
+ *
+ * Same as #TRACE_link_variable_add, but instead of providing the
+ * name of link to be considered, provide the source and destination
+ * hosts. All links that are part of the route between source and
+ * destination will have the value passed as parameter added to
+ * the current value of the variable name to be considered.
+ *
+ * \param src The name of the source host for get route.
+ * \param dst The name of the destination host for get route.
+ * \param variable The name of the variable to be considered.
+ * \param value The value to be added to the variable.
+ *
+ * \see TRACE_link_variable_declare, TRACE_link_srcdst_variable_set, TRACE_link_srcdst_variable_sub
+ */
+void TRACE_link_srcdst_variable_add (const char *src, const char *dst, const char *variable, double value)
+{
+ TRACE_link_srcdst_variable_add_with_time (MSG_get_clock(), src, dst, variable, value);
+}
+
+/** \ingroup TRACE_user_variables
+ * \brief Subtract a value from the variable present in the links connecting source and destination.
+ *
+ * Same as #TRACE_link_variable_sub, but instead of providing the
+ * name of link to be considered, provide the source and destination
+ * hosts. All links that are part of the route between source and
+ * destination will have the value passed as parameter subtracted from
+ * the current value of the variable name to be considered.
+ *
+ * \param src The name of the source host for get route.
+ * \param dst The name of the destination host for get route.
+ * \param variable The name of the variable to be considered.
+ * \param value The value to be subtracted from the variable.
+ *
+ * \see TRACE_link_variable_declare, TRACE_link_srcdst_variable_set, TRACE_link_srcdst_variable_add
+ */
+void TRACE_link_srcdst_variable_sub (const char *src, const char *dst, const char *variable, double value)