C `pthread`

# `pthread` Demo

The typical workflow of C pthread:

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


void *mythread(void *arg){
    printf("%s\n", (char*)arg);
    return NULL;
}

int main(int argc, char* argv[]){
    pthread_t p1, p2;
    int rc;
    printf("main: begin\n");
    rc = pthread_create(&p1, NULL, mythread, "A"); assert(rc == 0);
    rc = pthread_create(&p2, NULL, mythread, "B"); assert(rc == 0);

    rc = pthread_join(p1, NULL); assert(rc == 0);
    rc = pthread_join(p2, NULL); assert(rc == 0);

    printf("main: end\n");
    return 0;
}

where two functions are included, pthread_create for create new thread, pthread_join for waitting thread.

Thte prototype of pthread_create:

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

The created thread structure will be stored at thread.
attr specifies some attributes for the new created thread, default configuration is applied if it’s set to NULL.
function pointer start_routine is the function that will be executed by new thread.
arg is the arguments passing to start_routine.

The prototype of pthread_join:

int pthread_join(
    pthread_t thread,
    void**    value_ptr
)

The join function wait for thread to finish to continue.

C pthread

# pthread Demo

# pthread Race Condition

C `pthread`

# `pthread` Demo

# `pthread` Race Condition