Question : Write a code that prints "Are Roses Red?" in console. Your code should have S
threads. You will need semaphore for proper synchronization.
a. Thread one will print: "This"
b. Thread two will print: "is"
c. Thread three will print: "CSE207"
d.Thread four will print: "."
e. And thread 5 will print all necessary spaces.
All the task will be performed inside child process. The child process will print the
string "This is CSE207," After Finishing child process the parent process will print
"Program done"
Code:
#include <stdio.h>
#include <pthread.h>
#include <semaphore.h>
#include <sys/wait.h>
#include <unistd.h>
//#define THREAD_COUNT 10
sem_t mutex;
pthread_t thread1,thread2,thread3,thread4,thread5;
void *print1(){
sem_wait(&mutex);
printf("This ");
sem_post(&mutex);
pthread_exit(NULL);
}
void *print2(){
sem_wait(&mutex);
printf(" is ");
sem_post(&mutex);
pthread_exit(NULL);
}
void *print3(){
sem_wait(&mutex);
printf(" CSE207");
sem_post(&mutex);
pthread_exit(NULL);
}
void *print4(){
sem_wait(&mutex);
printf(".");
sem_post(&mutex);
pthread_exit(NULL);
}
void *print5(){
sem_wait(&mutex);
pthread_create(&thread1, NULL,print1, NULL);
pthread_create(&thread2, NULL,print2, NULL);
pthread_create(&thread3, NULL,print3,NULL);
pthread_create(&thread4, NULL,print4,NULL);
pthread_join(thread1, NULL);
pthread_join(thread2, NULL);
pthread_join(thread3, NULL);
pthread_join(thread4, NULL);
sem_post(&mutex);
pthread_exit(NULL);
}
int main(){
sem_init(&mutex,0,5);
pid_t pid = fork();
if(pid<0)
printf("\nERROR");
else if(pid==0){
printf("\nCHILD PROCESS EXCUTING");
printf("\n");
pthread_create(&thread5, NULL,print5,NULL);
pthread_join(thread5, NULL);
}
else{
wait(NULL);
printf("\nOPERATION DONE\n");
}
sem_destroy(&mutex);
}
Run :
