1. Pthreads void *sleeping(void *); /* thread routine */
#include <pthread.h>
pthread_t tid ; //thread id.
pthread_attr_t attr ;
void *sleeping(void *); /* thread routine */
main()
{ int time = 4;
pthread_create(&tid, NULL, sleeping, &time) ; }
void *sleeping((void *) sleep_time)
{ int *ptr ;
ptr = (int *) sleep_time ;
printf(“Getting ready to sleepfor %d secs\n”, *ptr) ;
sleep (*ptr) ;
printf(“Hello I’m BACK!!\n”) ;

2. Pthreads void *sleeping(void *); /* thread routine */
#include <pthread.h>
pthread_t tid ; //thread id.
pthread_attr_t attr ;
void *sleeping(void *); /* thread routine */
main()
{ int time = 4;
pthread_create(&tid, NULL, sleeping, &time) ; }
void *sleeping((void *) sleep_time)
{ int *ptr ;
ptr = (int *) sleep_time ; //type cast
printf(“Getting ready to sleepfor %d secs\n”, *ptr) ; //dereferencing
sleep (*ptr) ;
printf(“Hello I’m BACK!!\n”) ;

3. Problem: When main exits, all threads are terminated.
Solution: pthread_join(tid, NULL) //this waits for a //particular thread with id tid.
pthread_join(NULL) //waits for any thread.

4. #include <pthread.h>
pthread_t tid ; //thread id.
pthread_attr_t attr ;
void *sleeping(void *); /* thread routine */
main()
{ int time = 4;
pthread_create(&tid, NULL, sleeping, &time) ;
pthread_join(tid, NULL) ; }
void *sleeping((void *) sleep_time)
{ int *ptr ;
ptr = (int *) sleep_time ; //type cast
printf(“Getting ready to sleepfor %d secs\n”, *ptr) ; //dereferencing
sleep (*ptr) ;
printf(“Hello I’m BACK!!\n”) ;

5. pthread_t tids[10] ; main() { for (j = 0 ; j < 10 ; j++)
pthread_create(&tids[i], NULL, sleeping, &time) ;
for(j = 0 ; j < 10 ; j++)
pthread_join(tid[i], NULL) ; }

6. All theads share:
global variables
file descriptors
static variables within creating function.
Local variables are private to each thread.
void *sleeping(int * sleep_time)
{ static int tootoo = 10 ; //shared
int june ; //private
printf(“thread sleeping for %d secs\n”, *sleep_time) ;
tootoo++ ; //will have final value of 20. }