#include <pthread.h>
#include <signal.h>
//#include <sys/time.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>


typedef void (timer_callback) (union sigval);
/*
 * Timer initialization function 
 */
#define TIME_SET	1000
int timer_initialize(timer_t * timer_id, int period, timer_callback * cbf, void* data) 
{
int status =0;
struct itimerspec ts;
struct sigevent se;
    
	/* register callback func */
	se.sigev_notify = SIGEV_THREAD;
	se.sigev_value.sival_ptr = data;
	se.sigev_notify_function = cbf;
	se.sigev_notify_attributes = NULL;

	if(timer_create(CLOCK_REALTIME, &se, timer_id) != 0)
	{
		printf(" error in creating a timer %s", strerror(errno));
		exit(1);
	}

	/* assign the period */
	ts.it_value.tv_sec = period/1000;
	ts.it_value.tv_nsec = 0;
	ts.it_interval.tv_sec = ts.it_value.tv_sec;
        ts.it_interval.tv_nsec = ts.it_value.tv_nsec;

	if(timer_settime(*timer_id, 0, &ts, 0) != 0)
	{
		printf(" error in setting timer %s", strerror(errno));
		exit(1);
	}

return 0;
}
/*
 * scanTimer callback function 
 */
void scanTimer_callback(union sigval si)
{
    char* evt = (int*) si.sival_ptr;
    printf("\n Iam in [%s] callback \n", evt);
}

/*
 * tileTimer callback function 
 */
void tileTimer_callback(union sigval si)
{
    char* evt = (int*) si.sival_ptr;
    printf("\n Iam in [%s] callback \n", evt);
}
int main(int argc, char ** argv)
{

    timer_t timer_ID;
  while(1){
    timer_initialize(&timer_ID, TIME_SET, scanTimer_callback, (void *) "Scan" );
    getchar();
    timer_delete(timer_ID);
    getchar();
  }
    return 0;
}

#include <signal.h>
#include <time.h>
#include <string.h>
#include <stdio.h>

void callback(union sigval si)
{
   const char* data = si.sival_ptr;
   printf("\nInside callback; data is %s", data);
}

int main()
{
   timer_t timerID;

   struct sigevent se;

   memset(&se, 0, sizeof(se));

   se.sigev_notify            = SIGEV_THREAD;
   se.sigev_value.sival_ptr   = "Scan";
   se.sigev_notify_function   = callback;
   se.sigev_notify_attributes = NULL;

   if (timer_create(CLOCK_REALTIME, &se, &timerID) != 0)
   {
      perror("Error creating timer.");
      return -1;
   }

   struct itimerspec ts = { {2, 0}, {2, 0} };

   if (timer_settime(timerID, 0, &ts, NULL) != 0)
   {
      perror("Error setting up timer.");
      return -1;
   }

   printf("Press <enter> to continue...");
   getchar();

   timer_delete(timerID);

   printf("\n");

   return 0;
}