Programming

 
S1:
signal(synch);

 
wait(synch);
S2;

 
$ cat practise2.c
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <pthread.h>
#include <semaphore.h>
#include <sys/sem.h>
int count = 0;
int pargc;
char **pargv;
sem_t synch;
void *thread1(void *);
void *thread2(void *);
int main(int argc, char *argv[])
{
        pargc = argc;
        pargv = argv;
        if(argc != 3)
        {
                printf("Invalid no. of arguments!\n");
                exit(-1);
        }
        else
        {
        sem_init(&synch,count,0);
        pthread_t tid1;
        pthread_t tid2;
        int t1 = 1;
        int t2 = 2;
        pthread_attr_t attr1;
        pthread_attr_t attr2;
        pthread_attr_init(&attr1);
        pthread_attr_init(&attr2);
        {
        pthread_create(&tid1,&attr1,thread1,(void *)t1);
        pthread_create(&tid2,&attr2,thread2,(void *)t2);
        }
        {
        pthread_join(tid1,NULL);
        pthread_join(tid2,NULL);
        }
        printf("\nThreads finished!\n");
        }
        return 0;
}
void *thread1(void *n)
{
        int i;
        for(i = 0;i<5;i++)
        {
        printf("0\n");
        sem_post(&synch);
        }
        pthread_exit(0);
}
void *thread2(void *n)
{
        int i;
        for(i = 0;i<5;i++)
        {
        sem_wait(&synch);
        printf("1\n");
        }
        pthread_exit(0);
}

 
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