/*
         Creating and joining threads
*/
#define _GNU_SOURCE
#define _REENTRANT
#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#include <sys/types.h>
#include <sys/time.h>
#include <unistd.h>

int MAX=5;

int		my_rand( int, int );
void    *say_it( void * );


int main(int argc, char *argv[])
{
    pthread_t   thread_id[MAX];
    int			status, *p_status = &status;
	int			i;

    setvbuf(stdout, (char *) NULL, _IONBF, 0);
    
	if ( argc > MAX+1 )
    {                 // check arg list
        fprintf(stderr, "%s arg1, arg2, ... arg%d\n", argv[0], MAX);
        return 1;
    }
    
	printf("Displaying\n");
    
	for (i = 0; i < argc-1; ++i)
    {   // generate threads
        if( pthread_create(&thread_id[i],NULL,say_it,(void *)argv[i+1]) > 0)
        {
            fprintf(stderr, "pthread_create failure\n");
            return 2;
        }
    }
    
	for (i=0; i < argc-1; ++i)
    {      // wait for each thread
        if ( pthread_join(thread_id[i], (void **) p_status) > 0)
        {
            fprintf(stderr, "pthread_join failure\n");
            return 3;
        }
        printf("\nThread %d returns %d", thread_id[i], status);

    }
    
	printf("\nDone\n");
    return 0;
}

//   Display the word passed a random # of times
void * say_it(void *word)
{
    int i;
	
	int numb = my_rand(2,6);
	

    printf("%s\t to be printed %d times.\n", (char *)word, numb);

	sleep(1);

    for (i=0; i < numb; ++i)
    {
        //sleep(1);
        printf("%s ", (char *) word);
    }
	sleep(4);
    return (void *) NULL;
}

//   Generate a random # within given range
int my_rand(int start, int range)
{
    struct timeval t;
    gettimeofday(&t, (struct timezone *)NULL);
    return (int)(start+((float)range * rand_r((unsigned *)&t.tv_usec)) / (RAND_MAX+1.0));
}