Thread creation and management in Operating Systems - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a new thread using the POSIX pthread library.

Operating Systems

pthread_t thread_id;
pthread_create(&thread_id, NULL, [1], NULL);

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Apthread_join

Bstart_thread

Cmain

Dpthread_exit

Attempts:

3 left

💡 Hint

Common Mistakes

Using pthread_join or pthread_exit as the thread start function.

Passing main as the thread function.

The pthread_create function requires the name of the function that the new thread will execute. This function is passed as the third argument. Here, start_thread is the correct function name to start the thread.

2fill in blank

medium

Complete the code to wait for a thread to finish execution.

Operating Systems

pthread_t tid;
// thread created earlier
pthread_join([1], NULL);

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Athread_id

BNULL

C0

Dtid

Attempts:

3 left

💡 Hint

Common Mistakes

Passing NULL instead of the thread ID.

Using a variable name not declared as a thread ID.

The pthread_join function waits for the thread specified by its thread ID to finish. The thread ID variable here is tid.

3fill in blank

hard

Fix the error in the thread function declaration to match pthread requirements.

Operating Systems

void* [1](void* arg) {
    // thread code
    return NULL;
}

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Athread_func

Bvoid thread_func

CthreadFunc()

Dint thread_func

Attempts:

3 left

💡 Hint

Common Mistakes

Declaring the function with no parameters or wrong return type.

Using int or void return types instead of void*.

The thread function must return void* and accept a single void* argument. The correct declaration is void* thread_func(void* arg).

4fill in blank

hard

Fill both blanks to create a thread and wait for it to finish.

Operating Systems

pthread_t tid;
pthread_create(&tid, NULL, [1], NULL);
pthread_[2](tid, NULL);

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Athread_func

Bjoin

Cexit

Dstart

Attempts:

3 left

💡 Hint

Common Mistakes

Using pthread_exit instead of pthread_join to wait.

Passing wrong function names.

The thread is created with pthread_create using the function thread_func. To wait for the thread to finish, pthread_join is called with the thread ID.

5fill in blank

hard

Fill all three blanks to create a thread, pass an argument, and wait for it to finish.

Operating Systems

void* [1](void* arg) {
    int* num = (int*)[2];
    printf("Number: %d\n", *num);
    return NULL;
}

pthread_t tid;
int value = 5;
pthread_create(&tid, NULL, [3], &value);
pthread_join(tid, NULL);

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Athread_func

Barg

Dvalue

Attempts:

3 left

💡 Hint

Common Mistakes

Using different names for the argument pointer inside the function.

Passing wrong function names to pthread_create.

The thread function is named thread_func. Inside it, the argument pointer is named arg and cast to int*. The same function name thread_func is passed to pthread_create.