#include "xbt.h" /* calloc, printf */
#include "instr/instr_private.h"
+/** @addtogroup MSG_examples
+ *
+ * @section MSG_ex_actions Trace driven simulations
+ *
+ * The <b>actions/actions.c</b> example demonstrates how to run trace-driven simulations. It
+ * is very handy when you want to test an algorithm or protocol that
+ * does nothing unless it receives some events from outside. For
+ * example, a P2P protocol reacts to requests from the user, but
+ * does nothing if there is no such event.
+ *
+ * In such situations, SimGrid allows to write your protocol in your
+ * C file, and the events to react to in a separate text file.
+ * Declare a function handling each of the events that you want to
+ * accept in your trace files, register them using \ref
+ * MSG_action_register in your main, and then use \ref
+ * MSG_action_trace_run to launch the simulation. You can either
+ * have one trace file containing all your events, or a file per
+ * simulated process. Check the tesh files in the example directory
+ * for details on how to do it.
+ *
+ * This example uses this approach to replay MPI-like traces. It
+ * comes with a set of event handlers reproducing MPI events. This
+ * is somehow similar to SMPI, yet differently implemented. This
+ * code should probably be changed to use SMPI internals instead,
+ * but wasn't, so far.
+ *
+ */
+
XBT_LOG_NEW_DEFAULT_CATEGORY(actions,
"Messages specific for this msg example");
int communicator_size = 0;
