SAM Example 1

From SoOS

[edit] Description

This example shows how to start worker threads.

[edit] Code

#include <stdio.h>
#include <sam.h>
 
#define N 4
 
void * worker_routine(void *args)
{
  SAM_t sam_context; /* Declare a SAM context variable */
  void *myargs; /* Pointer to where the arguments are stored */
 
  /* Start the execution of this worker thread */
  /* Extract the SAM context and the arguments */
  SAM_Execution_start(args, &sam_context, &myargs);
 
  /* Print the SAM worker ID of this worker thread  */
  printf("SAM worker id: %d\n", (int)SAM_My_workid(sam_context));
 
  /* Finish the execution of this worker trhead */
  SAM_Execution_finish(sam_context);
 
  return NULL;
}
 
int main(void)
{
  SAM_t sam_context; /* Declare a SAM context variable */
  SAM_Workerid_t th[N]; /* For storing the worker threads ID's  */
  void *result; /* Gets the result of the worker thread */
  int i;
 
  /* Initialize the SAM context */
  SAM_Init(&sam_context);
 
 
  for(i=0;i<N;i++)
    {
      /* Create the worker threads running worker_routine  */
      th[i] = SAM_Execution_create(sam_context, *worker_routine, NULL);
    }
 
 
  for(i=0;i<N;i++)
    {
      /* Join the worker threads and get the result */
      result = (int *)SAM_Execution_join(sam_context, th[i]);
    }
 
  /* Destroy the SAM context */
  SAM_Destroy(&sam_context);
 
  return 0;
}

[edit] Explanation

This example shows how to start worker threads. In line 38 is the call to function SAM_Execution_create() to create a worker thread. It is called many times to create many worker threads. Later we have to join all of them as shown in line 45 by calling function SAM_Execution_join().

The routine for the worker threads starts in line 6 (the function worker_routine()). The first thing it must do is call SAM_Execution_start() (line 13) to set up correctly the thread and to retrieve the SAM context and the arguments. It must finish by calling SAM_Execution_finish() (line 19) just before returning.

[edit] Compile Command

gcc example1.c -lsam -lpthread -o example1

[edit] Download

example1.c