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Dobre, 

takze jsem zatim udelal neco takoveho - predavani dat je pres spolecny buffer:

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

#define NUM_OF_WORKERS  3

#define NUM_WORKERS_JOB 5
#define JOB_MAX_TIME 10

#define MESSAGE_FOR_BOSS_LENGTH 80
char message_for_boss[MESSAGE_FOR_BOSS_LENGTH];

pthread_mutex_t message_for_boss_mutex;


void *worker_thread (void* t)
{
    int job;
    unsigned int random_time;

    printf ("W%i: Hello!\n", (unsigned int)t);

    for (job = 0; job < NUM_WORKERS_JOB; job++)
    {
        random_time = rand () % JOB_MAX_TIME;

        printf ("W%i: I will complete my job #%i after %i seconds.\n", (unsigned int)t, job, random_time);

        /* Simulate a job progress */
        sleep(random_time);

        /* Sent message for my Boss */
        pthread_mutex_lock (&message_for_boss_mutex);
        sprintf (message_for_boss, "Hi, there is W%i! My job #%i is completed! Processing time was %i seconds.", (unsigned int)t, job, random_time);
        pthread_mutex_unlock (&message_for_boss_mutex);

        printf ("W%i: I have completed my job #%i.\n", (unsigned int)t, job);
    }

    printf ("W%i: Good bye!\n", (unsigned int)t);

    pthread_exit (NULL);
}


int main (int argc, char **argv)
{
    unsigned int i;

    pthread_t threads[NUM_OF_WORKERS];
    pthread_attr_t attr;

    /* Initialize mutex */
    pthread_mutex_init(&message_for_boss_mutex, NULL);

    /* For portability, explicitly create threads in a joinable state */
    pthread_attr_init(&attr);
    pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE);

    for (i = 0; i < NUM_OF_WORKERS; i++)
    {
        printf ("B: Creating worker thread W%i\n", i);
        pthread_create (&threads[i], &attr, worker_thread, (void *)i);
    }

    /* Wait for result from worker_thread */
    printf ("B: Waiting for messages from workers.\n");


    /* Wait for all threads to complete */
    for (i = 0; i < NUM_OF_WORKERS; i++) {
        pthread_join(threads[i], NULL);
    }

    printf ("B: All worker threads are joined!\n");

    /* Destroy mutex */
    pthread_mutex_destroy(&message_for_boss_mutex);

    return (0);
}


jeste ale nechapu tu spolecnou condition variable - pokud bosse probudi cekani pthread_cond_wait na spolecnou podminku, tak jakym zpusobem se on potom dozvi, ktery worker ho probudil?

Jinak jeste bych zaroven poprosil o zbeznou kontrolu tohoto, co uz mam - jsem v programovani v podstate samouk, takze si nejsem jisty, zda to delam tak spravne.

Dekuji, Tomas