1 /* Copyright (c) 2004, 2005, 2006, 2007, 2008, 2009, 2010. The SimGrid Team.
2 * All rights reserved. */
4 /* This program is free software; you can redistribute it and/or modify it
5 * under the terms of the license (GNU LGPL) which comes with this package. */
8 #include "xbt/sysdep.h"
14 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(msg_gos, msg,
15 "Logging specific to MSG (gos)");
17 /** \ingroup msg_gos_functions
19 * \brief Return the last value returned by a MSG function (except
22 MSG_error_t MSG_get_errno(void)
24 return PROCESS_GET_ERRNO();
27 /** \ingroup msg_gos_functions
28 * \brief Executes a task and waits for its termination.
30 * This function is used for describing the behavior of an agent. It
31 * takes only one parameter.
32 * \param task a #m_task_t to execute on the location on which the
34 * \return #MSG_FATAL if \a task is not properly initialized and
37 MSG_error_t MSG_task_execute(m_task_t task)
39 simdata_task_t simdata = NULL;
40 m_process_t self = MSG_process_self();
43 simdata = task->simdata;
45 xbt_assert0(simdata->host_nb == 0,
46 "This is a parallel task. Go to hell.");
49 TRACE_msg_task_execute_start(task);
52 xbt_assert1((!simdata->compute) && (task->simdata->isused == 0),
53 "This task is executed somewhere else. Go fix your code! %d",
54 task->simdata->isused);
56 DEBUG1("Computing on %s", MSG_process_self()->simdata->m_host->name);
58 if (simdata->computation_amount == 0) {
60 TRACE_msg_task_execute_end(task);
66 SIMIX_req_host_execute(task->name, SIMIX_host_self(),
67 simdata->computation_amount);
68 SIMIX_req_host_execution_set_priority(simdata->compute, simdata->priority);
70 SIMIX_req_set_category(simdata->compute, task->category);
73 self->simdata->waiting_action = simdata->compute;
74 SIMIX_req_host_execution_wait(simdata->compute);
75 self->simdata->waiting_action = NULL;
79 DEBUG2("Execution task '%s' finished in state %d", task->name, SIMIX_req_host_execution_get_state(task->simdata->compute));
80 if (SIMIX_req_host_execution_get_state(task->simdata->compute) == SIMIX_DONE) {
81 /* action ended, set comm and compute = NULL, the actions is already destroyed in the main function */
82 SIMIX_req_host_execution_destroy(task->simdata->compute);
83 simdata->computation_amount = 0.0;
85 simdata->compute = NULL;
87 TRACE_msg_task_execute_end(task);
90 } else if (SIMIX_req_host_get_state(SIMIX_host_self()) == 0) {
91 /* action ended, set comm and compute = NULL, the actions is already destroyed in the main function */
92 SIMIX_req_host_execution_destroy(task->simdata->compute);
94 simdata->compute = NULL;
96 TRACE_msg_task_execute_end(task);
98 MSG_RETURN(MSG_HOST_FAILURE);
100 /* action ended, set comm and compute = NULL, the actions is already destroyed in the main function */
101 SIMIX_req_host_execution_destroy(task->simdata->compute);
102 simdata->comm = NULL;
103 simdata->compute = NULL;
105 TRACE_msg_task_execute_end(task);
107 MSG_RETURN(MSG_TASK_CANCELLED);
111 /** \ingroup m_task_management
112 * \brief Creates a new #m_task_t (a parallel one....).
114 * A constructor for #m_task_t taking six arguments and returning the
115 corresponding object.
116 * \param name a name for the object. It is for user-level information
118 * \param host_nb the number of hosts implied in the parallel task.
119 * \param host_list an array of \p host_nb m_host_t.
120 * \param computation_amount an array of \p host_nb
121 doubles. computation_amount[i] is the total number of operations
122 that have to be performed on host_list[i].
123 * \param communication_amount an array of \p host_nb* \p host_nb doubles.
124 * \param data a pointer to any data may want to attach to the new
125 object. It is for user-level information and can be NULL. It can
126 be retrieved with the function \ref MSG_task_get_data.
128 * \return The new corresponding object.
131 MSG_parallel_task_create(const char *name, int host_nb,
132 const m_host_t * host_list,
133 double *computation_amount,
134 double *communication_amount, void *data)
137 simdata_task_t simdata = xbt_new0(s_simdata_task_t, 1);
138 m_task_t task = xbt_new0(s_m_task_t, 1);
139 task->simdata = simdata;
142 task->name = xbt_strdup(name);
146 simdata->computation_amount = 0;
147 simdata->message_size = 0;
148 simdata->compute = NULL;
149 simdata->comm = NULL;
150 simdata->rate = -1.0;
152 simdata->sender = NULL;
153 simdata->receiver = NULL;
154 simdata->source = NULL;
156 simdata->host_nb = host_nb;
157 simdata->host_list = xbt_new0(smx_host_t, host_nb);
158 simdata->comp_amount = computation_amount;
159 simdata->comm_amount = communication_amount;
161 for (i = 0; i < host_nb; i++)
162 simdata->host_list[i] = host_list[i]->simdata->smx_host;
167 MSG_error_t MSG_parallel_task_execute(m_task_t task)
169 simdata_task_t simdata = NULL;
170 m_process_t self = MSG_process_self();
173 simdata = task->simdata;
175 xbt_assert0((!simdata->compute)
176 && (task->simdata->isused == 0),
177 "This task is executed somewhere else. Go fix your code!");
179 xbt_assert0(simdata->host_nb,
180 "This is not a parallel task. Go to hell.");
182 DEBUG1("Parallel computing on %s", MSG_process_self()->simdata->m_host->name);
187 SIMIX_req_host_parallel_execute(task->name, simdata->host_nb,
189 simdata->comp_amount,
190 simdata->comm_amount, 1.0, -1.0);
191 DEBUG1("Parallel execution action created: %p", simdata->compute);
193 self->simdata->waiting_action = simdata->compute;
194 SIMIX_req_host_execution_wait(simdata->compute);
195 self->simdata->waiting_action = NULL;
197 DEBUG2("Finished waiting for execution of action %p, state = %d", simdata->compute, SIMIX_req_host_execution_get_state(task->simdata->compute));
201 if (SIMIX_req_host_execution_get_state(task->simdata->compute) == SIMIX_DONE) {
202 /* action ended, set comm and compute = NULL, the actions is already destroyed in the main function */
203 SIMIX_req_host_execution_destroy(task->simdata->compute);
204 simdata->computation_amount = 0.0;
205 simdata->comm = NULL;
206 simdata->compute = NULL;
208 } else if (SIMIX_req_host_get_state(SIMIX_host_self()) == 0) {
209 /* action ended, set comm and compute = NULL, the actions is already destroyed in the main function */
210 SIMIX_req_host_execution_destroy(task->simdata->compute);
211 simdata->comm = NULL;
212 simdata->compute = NULL;
213 MSG_RETURN(MSG_HOST_FAILURE);
215 /* action ended, set comm and compute = NULL, the actions is already destroyed in the main function */
216 SIMIX_req_host_execution_destroy(task->simdata->compute);
217 simdata->comm = NULL;
218 simdata->compute = NULL;
219 MSG_RETURN(MSG_TASK_CANCELLED);
224 /** \ingroup msg_gos_functions
225 * \brief Sleep for the specified number of seconds
227 * Makes the current process sleep until \a time seconds have elapsed.
229 * \param nb_sec a number of second
231 MSG_error_t MSG_process_sleep(double nb_sec)
234 /*m_process_t proc = MSG_process_self();*/
237 TRACE_msg_process_sleep_in(MSG_process_self());
240 /* create action to sleep */
241 state = SIMIX_req_process_sleep(nb_sec);
243 /*proc->simdata->waiting_action = act_sleep;
245 FIXME: check if not setting the waiting_action breaks something on msg
247 proc->simdata->waiting_action = NULL;*/
249 if (state == SIMIX_DONE) {
250 if (SIMIX_req_host_get_state(SIMIX_host_self()) == SURF_RESOURCE_OFF) {
252 TRACE_msg_process_sleep_out(MSG_process_self());
254 MSG_RETURN(MSG_HOST_FAILURE);
258 TRACE_msg_process_sleep_out(MSG_process_self());
260 MSG_RETURN(MSG_HOST_FAILURE);
263 TRACE_msg_process_sleep_out(MSG_process_self());
268 /** \ingroup msg_gos_functions
269 * \brief Listen on \a channel and waits for receiving a task from \a host.
271 * It takes three parameters.
272 * \param task a memory location for storing a #m_task_t. It will
273 hold a task when this function will return. Thus \a task should not
274 be equal to \c NULL and \a *task should be equal to \c NULL. If one of
275 those two condition does not hold, there will be a warning message.
276 * \param channel the channel on which the agent should be
277 listening. This value has to be >=0 and < than the maximal
278 number of channels fixed with MSG_set_channel_number().
279 * \param host the host that is to be watched.
280 * \return #MSG_FATAL if \a task is equal to \c NULL, #MSG_WARNING
281 if \a *task is not equal to \c NULL, and #MSG_OK otherwise.
284 MSG_task_get_from_host(m_task_t * task, m_channel_t channel, m_host_t host)
286 return MSG_task_get_ext(task, channel, -1, host);
289 /** \ingroup msg_gos_functions
290 * \brief Listen on a channel and wait for receiving a task.
292 * It takes two parameters.
293 * \param task a memory location for storing a #m_task_t. It will
294 hold a task when this function will return. Thus \a task should not
295 be equal to \c NULL and \a *task should be equal to \c NULL. If one of
296 those two condition does not hold, there will be a warning message.
297 * \param channel the channel on which the agent should be
298 listening. This value has to be >=0 and < than the maximal
299 number of channels fixed with MSG_set_channel_number().
300 * \return #MSG_FATAL if \a task is equal to \c NULL, #MSG_WARNING
301 * if \a *task is not equal to \c NULL, and #MSG_OK otherwise.
303 MSG_error_t MSG_task_get(m_task_t * task, m_channel_t channel)
305 return MSG_task_get_with_timeout(task, channel, -1);
308 /** \ingroup msg_gos_functions
309 * \brief Listen on a channel and wait for receiving a task with a timeout.
311 * It takes three parameters.
312 * \param task a memory location for storing a #m_task_t. It will
313 hold a task when this function will return. Thus \a task should not
314 be equal to \c NULL and \a *task should be equal to \c NULL. If one of
315 those two condition does not hold, there will be a warning message.
316 * \param channel the channel on which the agent should be
317 listening. This value has to be >=0 and < than the maximal
318 number of channels fixed with MSG_set_channel_number().
319 * \param max_duration the maximum time to wait for a task before giving
320 up. In such a case, #MSG_TRANSFER_FAILURE will be returned, \a task
321 will not be modified and will still be
322 equal to \c NULL when returning.
323 * \return #MSG_FATAL if \a task is equal to \c NULL, #MSG_WARNING
324 if \a *task is not equal to \c NULL, and #MSG_OK otherwise.
327 MSG_task_get_with_timeout(m_task_t * task, m_channel_t channel,
330 return MSG_task_get_ext(task, channel, max_duration, NULL);
333 /** \defgroup msg_gos_functions MSG Operating System Functions
334 * \brief This section describes the functions that can be used
335 * by an agent for handling some task.
339 MSG_task_get_ext(m_task_t * task, m_channel_t channel, double timeout,
342 xbt_assert1((channel >= 0)
343 && (channel < msg_global->max_channel), "Invalid channel %d",
347 MSG_mailbox_get_task_ext(MSG_mailbox_get_by_channel
348 (MSG_host_self(), channel), task, host,
353 MSG_task_receive_from_host(m_task_t * task, const char *alias,
356 return MSG_task_receive_ext(task, alias, -1, host);
359 MSG_error_t MSG_task_receive(m_task_t * task, const char *alias)
361 return MSG_task_receive_with_timeout(task, alias, -1);
365 MSG_task_receive_with_timeout(m_task_t * task, const char *alias,
368 return MSG_task_receive_ext(task, alias, timeout, NULL);
372 MSG_task_receive_ext(m_task_t * task, const char *alias, double timeout,
376 ("MSG_task_receive_ext: Trying to receive a message on mailbox '%s'",
378 return MSG_mailbox_get_task_ext(MSG_mailbox_get_by_alias(alias), task,
382 /** \ingroup msg_gos_functions
383 * \brief Send a task on a channel.
385 * This function takes two parameter.
386 * \param task a #m_task_t to send on another location.
387 * \param alias the channel on which the agent should put this
388 task. This value has to be >=0 and < than the maximal number of
389 channels fixed with MSG_set_channel_number().
390 * \return the msg_comm_t communication.
392 msg_comm_t MSG_task_isend(m_task_t task, const char *alias)
394 simdata_task_t t_simdata = NULL;
395 m_process_t process = MSG_process_self();
396 msg_mailbox_t mailbox = MSG_mailbox_get_by_alias(alias);
400 /* FIXME: these functions are not tracable */
402 /* Prepare the task to send */
403 t_simdata = task->simdata;
404 t_simdata->sender = process;
405 t_simdata->source = MSG_host_self();
407 xbt_assert0(t_simdata->isused == 0,
408 "This task is still being used somewhere else. You cannot send it now. Go fix your code!");
411 msg_global->sent_msg++;
413 /* Send it by calling SIMIX network layer */
415 SIMIX_req_comm_isend(mailbox, t_simdata->message_size,
416 t_simdata->rate, task, sizeof(void *), NULL, NULL);
417 return t_simdata->comm;
420 /** \ingroup msg_gos_functions
421 * \brief Listen on a channel for receiving a task from an asynchronous communication.
423 * It takes two parameters.
424 * \param task a memory location for storing a #m_task_t.
425 * \param alias the channel on which the agent should be
426 listening. This value has to be >=0 and < than the maximal
427 number of channels fixed with MSG_set_channel_number().
428 * \return the msg_comm_t communication.
430 msg_comm_t MSG_task_irecv(m_task_t * task, const char *alias)
432 smx_rdv_t rdv = MSG_mailbox_get_by_alias(alias);
436 /* FIXME: these functions are not tracable */
439 xbt_assert0(task, "Null pointer for the task storage");
443 ("MSG_task_get() was asked to write in a non empty task struct.");
445 /* Try to receive it by calling SIMIX network layer */
446 return SIMIX_req_comm_irecv(rdv, task, NULL, NULL, NULL);
449 /** \ingroup msg_gos_functions
450 * \brief Returns whether a communication is finished.
451 * \param comm the communication to test
452 * \return TRUE if the communication is finished
453 * (but it may have failed, use MSG_comm_get_status() to know its status)
454 * or FALSE if the communication is not finished yet
455 * If the status is FALSE, don't forget to use MSG_process_sleep() after the test.
457 int MSG_comm_test(msg_comm_t comm)
462 finished = SIMIX_req_comm_test(comm);
465 switch (e.category) {
481 /** \ingroup msg_gos_functions
482 * \brief This function checks if a communication is finished
483 * \param comms a vector of communications
484 * \return the position of the finished communication if any
485 * (but it may have failed, use MSG_comm_get_status() to know its status),
486 * or -1 if none is finished
488 int MSG_comm_testany(xbt_dynar_t comms)
491 int finished_index = -1;
493 finished_index = SIMIX_req_comm_testany(comms);
496 switch (e.category) {
501 finished_index = e.value;
509 return finished_index;
512 /** \ingroup msg_gos_functions
513 * \brief After received TRUE to MSG_comm_test(), the communication should be destroyed.
515 * It takes one parameter.
516 * \param comm the communication to destroy.
518 void MSG_comm_destroy(msg_comm_t comm)
520 if (SIMIX_req_comm_get_src_proc(comm) != SIMIX_process_self()) {
522 task = (m_task_t) SIMIX_req_comm_get_src_buff(comm);
523 task->simdata->isused=0;
525 SIMIX_req_comm_destroy(comm);
528 /** \ingroup msg_gos_functions
529 * \brief Wait for the completion of a communication.
531 * It takes two parameters.
532 * \param comm the communication to wait.
533 * \param timeout Wait until the communication terminates or the timeout occurs
534 * \return MSG_error_t
536 MSG_error_t MSG_comm_wait(msg_comm_t comm, double timeout)
539 MSG_error_t res = MSG_OK;
541 SIMIX_req_comm_wait(comm, timeout);
543 if (SIMIX_req_comm_get_src_proc(comm) != SIMIX_process_self()) {
545 task = (m_task_t) SIMIX_req_comm_get_src_buff(comm);
546 task->simdata->isused=0;
549 /* FIXME: these functions are not tracable */
552 switch (e.category) {
554 res = MSG_HOST_FAILURE;
557 res = MSG_TRANSFER_FAILURE;
570 /** \ingroup msg_gos_functions
571 * \brief This function is called by a sender and permit to wait for each communication
573 * It takes three parameters.
574 * \param comm a vector of communication
575 * \param nb_elem is the size of the comm vector
576 * \param timeout for each call of MSG_comm_wait
578 void MSG_comm_waitall(msg_comm_t * comm, int nb_elem, double timeout)
581 for (i = 0; i < nb_elem; i++) {
582 MSG_comm_wait(comm[i], timeout);
586 /** \ingroup msg_gos_functions
587 * \brief This function wait for the first completed communication
589 * It takes on parameter.
590 * \param comms a vector of communication
591 * \return the position of the completed communication from the xbt_dynar_t.
593 int MSG_comm_waitany(xbt_dynar_t comms)
596 int finished_index = -1;
598 finished_index = SIMIX_req_comm_waitany(comms);
601 switch (e.category) {
606 finished_index = e.value;
612 return finished_index;
616 * \ingroup msg_gos_functions
617 * \brief Returns the error (if any) that occured during a finished communication.
618 * \param comm a finished communication
619 * \return the status of the communication, or MSG_OK if the communication
620 * was successfully completed
622 MSG_error_t MSG_comm_get_status(msg_comm_t comm) {
625 e_smx_state_t smx_state = SIMIX_req_comm_get_state(comm);
630 result = MSG_TASK_CANCELLED;
634 case SIMIX_SRC_HOST_FAILURE:
635 case SIMIX_DST_HOST_FAILURE:
636 result = MSG_HOST_FAILURE;
639 case SIMIX_LINK_FAILURE:
640 result = MSG_TRANSFER_FAILURE;
643 case SIMIX_SRC_TIMEOUT:
644 case SIMIX_DST_TIMEOUT:
645 result = MSG_TIMEOUT;
655 m_task_t MSG_comm_get_task(msg_comm_t comm)
657 xbt_assert0(comm, "Invalid parameters");
658 return (m_task_t) SIMIX_req_comm_get_src_buff(comm);
661 /** \ingroup msg_gos_functions
662 * \brief Put a task on a channel of an host and waits for the end of the
665 * This function is used for describing the behavior of an agent. It
666 * takes three parameter.
667 * \param task a #m_task_t to send on another location. This task
668 will not be usable anymore when the function will return. There is
669 no automatic task duplication and you have to save your parameters
670 before calling this function. Tasks are unique and once it has been
671 sent to another location, you should not access it anymore. You do
672 not need to call MSG_task_destroy() but to avoid using, as an
673 effect of inattention, this task anymore, you definitely should
674 renitialize it with #MSG_TASK_UNINITIALIZED. Note that this task
675 can be transfered iff it has been correctly created with
677 * \param dest the destination of the message
678 * \param channel the channel on which the agent should put this
679 task. This value has to be >=0 and < than the maximal number of
680 channels fixed with MSG_set_channel_number().
681 * \return #MSG_FATAL if \a task is not properly initialized and
682 * #MSG_OK otherwise. Returns #MSG_HOST_FAILURE if the host on which
683 * this function was called was shut down. Returns
684 * #MSG_TRANSFER_FAILURE if the transfer could not be properly done
685 * (network failure, dest failure)
687 MSG_error_t MSG_task_put(m_task_t task, m_host_t dest, m_channel_t channel)
689 return MSG_task_put_with_timeout(task, dest, channel, -1.0);
692 /** \ingroup msg_gos_functions
693 * \brief Does exactly the same as MSG_task_put but with a bounded transmition
699 MSG_task_put_bounded(m_task_t task, m_host_t dest, m_channel_t channel,
702 task->simdata->rate = maxrate;
703 return MSG_task_put(task, dest, channel);
706 /** \ingroup msg_gos_functions \brief Put a task on a channel of an
707 * host (with a timeout on the waiting of the destination host) and
708 * waits for the end of the transmission.
710 * This function is used for describing the behavior of an agent. It
711 * takes four parameter.
712 * \param task a #m_task_t to send on another location. This task
713 will not be usable anymore when the function will return. There is
714 no automatic task duplication and you have to save your parameters
715 before calling this function. Tasks are unique and once it has been
716 sent to another location, you should not access it anymore. You do
717 not need to call MSG_task_destroy() but to avoid using, as an
718 effect of inattention, this task anymore, you definitely should
719 renitialize it with #MSG_TASK_UNINITIALIZED. Note that this task
720 can be transfered iff it has been correctly created with
722 * \param dest the destination of the message
723 * \param channel the channel on which the agent should put this
724 task. This value has to be >=0 and < than the maximal number of
725 channels fixed with MSG_set_channel_number().
726 * \param timeout the maximum time to wait for a task before giving
727 up. In such a case, #MSG_TRANSFER_FAILURE will be returned, \a task
729 * \return #MSG_FATAL if \a task is not properly initialized and
730 #MSG_OK otherwise. Returns #MSG_HOST_FAILURE if the host on which
731 this function was called was shut down. Returns
732 #MSG_TRANSFER_FAILURE if the transfer could not be properly done
733 (network failure, dest failure, timeout...)
736 MSG_task_put_with_timeout(m_task_t task, m_host_t dest,
737 m_channel_t channel, double timeout)
739 xbt_assert1((channel >= 0)
740 && (channel < msg_global->max_channel), "Invalid channel %d",
743 DEBUG1("MSG_task_put_with_timout: Trying to send a task to '%s'", dest->name);
745 MSG_mailbox_put_with_timeout(MSG_mailbox_get_by_channel
746 (dest, channel), task, timeout);
749 MSG_error_t MSG_task_send(m_task_t task, const char *alias)
751 DEBUG1("MSG_task_send: Trying to send a message on mailbox '%s'", alias);
752 return MSG_task_send_with_timeout(task, alias, -1);
757 MSG_task_send_bounded(m_task_t task, const char *alias, double maxrate)
759 task->simdata->rate = maxrate;
760 return MSG_task_send(task, alias);
765 MSG_task_send_with_timeout(m_task_t task, const char *alias,
768 return MSG_mailbox_put_with_timeout(MSG_mailbox_get_by_alias(alias),
772 int MSG_task_listen(const char *alias)
776 return !MSG_mailbox_is_empty(MSG_mailbox_get_by_alias(alias));
779 /** \ingroup msg_gos_functions
780 * \brief Test whether there is a pending communication on a channel.
782 * It takes one parameter.
783 * \param channel the channel on which the agent should be
784 listening. This value has to be >=0 and < than the maximal
785 number of channels fixed with MSG_set_channel_number().
786 * \return 1 if there is a pending communication and 0 otherwise
788 int MSG_task_Iprobe(m_channel_t channel)
790 xbt_assert1((channel >= 0)
791 && (channel < msg_global->max_channel), "Invalid channel %d",
797 !MSG_mailbox_is_empty(MSG_mailbox_get_by_channel
798 (MSG_host_self(), channel));
801 /** \ingroup msg_gos_functions
803 * \brief Return the number of tasks waiting to be received on a \a
804 channel and sent by \a host.
806 * It takes two parameters.
807 * \param channel the channel on which the agent should be
808 listening. This value has to be >=0 and < than the maximal
809 number of channels fixed with MSG_set_channel_number().
810 * \param host the host that is to be watched.
811 * \return the number of tasks waiting to be received on \a channel
814 int MSG_task_probe_from_host(int channel, m_host_t host)
816 xbt_assert1((channel >= 0)
817 && (channel < msg_global->max_channel), "Invalid channel %d",
823 MSG_mailbox_get_count_host_waiting_tasks(MSG_mailbox_get_by_channel
824 (MSG_host_self(), channel),
829 int MSG_task_listen_from_host(const char *alias, m_host_t host)
834 MSG_mailbox_get_count_host_waiting_tasks(MSG_mailbox_get_by_alias
838 /** \ingroup msg_gos_functions
839 * \brief Test whether there is a pending communication on a channel, and who sent it.
841 * It takes one parameter.
842 * \param channel the channel on which the agent should be
843 listening. This value has to be >=0 and < than the maximal
844 number of channels fixed with MSG_set_channel_number().
845 * \return -1 if there is no pending communication and the PID of the process who sent it otherwise
847 int MSG_task_probe_from(m_channel_t channel)
853 xbt_assert1((channel >= 0)
854 && (channel < msg_global->max_channel), "Invalid channel %d",
859 MSG_mailbox_get_head(MSG_mailbox_get_by_channel
860 (MSG_host_self(), channel))))
863 return MSG_process_get_PID(task->simdata->sender);
866 int MSG_task_listen_from(const char *alias)
873 (task = MSG_mailbox_get_head(MSG_mailbox_get_by_alias(alias))))
876 return MSG_process_get_PID(task->simdata->sender);