root/pthread/dining-mt.c

DEFINITIONS

1. philosopher
2. main

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

pthread_mutex_t forks[5];

void philosopher(int *ip)
{
        pthread_mutex_t *sol,*sag;
        int i=*ip;
        int z;

        printf("philosopher %d thread id %u started\n", i,
                        pthread_self()); 
        sol=i==0?forks+4:forks+(i-1);
        sag=forks+i;
        srand(i+time(NULL));
        for (z=0;z<100;z++) {
//              usleep(rand()%10);
                pthread_mutex_lock(sol);
                pthread_mutex_lock(sag);
                printf("Philosopher %d is eating %d\n",i,z);
                usleep(10000); //rand()%30000+10000);
                printf("Philosopher %d finished eating %d\n",i,z);
                pthread_mutex_unlock(sol);
                pthread_mutex_unlock(sag);
        }
}

int main() 
{
        pthread_t phils[5];
        int phids[5]={0,1,2,3,4};
        int i,n;
        
        for (i=0;i<5;i++) {
                if (pthread_mutex_init(&(forks[i]),NULL)) {
                        perror("Creating mutex");
                        return(-1);
                }
        }
        for (i=0;i<5;i++) {
                if (pthread_create(&(phils[i]), NULL, 
                        philosopher, (void *) &(phids[i])) )
                        perror("Create failed");
        }
        for (i=0;i<5;i++) {
                pthread_join(phils[i],NULL);
        }
        sleep(1);
}