Basic implementation of multi-threading in C language

The basic implementation of multi-threading in C language can be done using the pthread library.

Firstly, the pthread.h header file needs to be included in the program.

#include <pthread.h>

Next, it is necessary to create a thread function to execute the tasks of multi-threading. The definition of the thread function is as follows:

void* thread_function(void* arg) {
    // 线程的任务代码
    // ...
    return NULL;
}

Please note that the return type of a thread function is a void pointer, which can be used to pass the result of the thread.

Next, create and run threads in the main function. Thread creation can be done using the pthread_create function, defined as follows:

int pthread_create(pthread_t* thread, const pthread_attr_t* attr, void* (*start_routine)(void*), void* arg);

“thread is a pointer to the pthread_t type used to store the thread’s ID. attr is a pointer to the pthread_attr_t type used to set the thread’s attributes. start_routine refers to the thread function defined above, with arg being the parameter passed to the thread function.”

Here is an example code for creating and running multiple threads:

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

void* thread_function(void* arg) {
    int thread_id = *(int*)arg;
    printf("Thread %d is running\n", thread_id);
    return NULL;
}

int main() {
    pthread_t threads[10];
    int thread_ids[10];

    for (int i = 0; i < 10; ++i) {
        thread_ids[i] = i;
        pthread_create(&threads[i], NULL, thread_function, &thread_ids[i]);
    }

    for (int i = 0; i < 10; ++i) {
        pthread_join(threads[i], NULL);
    }

    return 0;
}

In the example above, 10 threads are created and the thread IDs are passed to the thread function through the thread_ids array. Then, the pthread_create function is used to create the threads and the pthread_join function is used to wait for all threads to finish running.

The above is the basic implementation of multithreading in C language. Using the pthread library, it is easy to create and manage multiple threads for concurrent programming.