thread

#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#include <malloc.h>

struct range
{
	int threadnumber;
	unsigned long start;
	unsigned long end ;

};

void * function(void *ptr)
{
   struct range *rptr;
   rptr=(struct range *)ptr;

   printf("\n Thread number: %d,start : %lu,end :%lu",rptr->threadnumber,rptr->start,rptr->end);

}

int main()
{
     pthread_t *threadid;

     int i,j,threadcount;

     unsigned long start[3];
     unsigned long end[3];

     struct range **Rangearr;

     printf("\n Enter the number of threads to run : ");
     scanf("%d",&threadcount);

     Rangearr=(struct range **)malloc(threadcount*sizeof(struct range *));

     threadid=(pthread_t *)malloc(threadcount * sizeof(pthread_t) );

     for(i=0;i<threadcount;i++)
     {
    	 start[i]=i;
    	 end[i]=i+3;
    	 threadid[i]=i;


     }


     for(i=0;i<threadcount;i++)
     {
    	 Rangearr[i]=(struct range *)malloc(sizeof(struct range));
    	 Rangearr[i]->start=start[i];
    	 Rangearr[i]->end=end[i];
    	 Rangearr[i]->threadnumber=i;


     }

     for(i=0;i<threadcount;i++)
     {
    	 pthread_create(&threadid[i],NULL,function,(void *) Rangearr[i]);
     }


      for(j=0;j<threadcount;j++)
      {
    	  pthread_join(threadid[j], NULL);
      }

      free( Rangearr);
      free(threadid);
}