In C, a thread is a basic unit of execution of any process. It refers to the use of many threads inside a single process, with each thread serving a separate function. Multithreading in C can be used to improve the working of an application through parallelism, making it easy to perform more than one task simultaneously.
To create a thread in C, you need to include the header file pthread and declare an object of type pthread_t. The pthread_create() function is then used to create a thread, which takes four arguments: a pointer to the thread ID, attributes, a pointer to the function to be executed by the thread, and a pointer to the argument to be passed to the function.
Once created, threads are peers and may create other threads. There is no implied hierarchy or dependency between threads. To exit a thread, pthread_exit() is used, which is usually written at the end of the starting routine. A parent thread can wait for a child thread using pthread_join(), which takes the ID of the thread that the parent thread waits for and a reference to the return value.
