C++ System Programming Cookbook

How to do it...

In this recipe, we'll create a multi-threaded program to increment an integer until it reaches 200000. Again, the code section that takes care of the increments must be protected and we'll use POSIX semaphores. The main method will create the two threads and ensure that the resources are destroyed correctly. Let's get started:

1. Let's open a new file called posixSemaphore.cpp and develop the structure and the critical section method:

#include <pthread.h>#include <semaphore.h>#include <iostream>struct ThreadInfo{    sem_t sem;    int counter;};void* increment(void *arg){    ThreadInfo* info = static_cast<ThreadInfo*>(arg);    sem_wait(&info->sem);    std::cout << "Thread Started ... " << std::endl;    for (int i = 0; i < 100000; ++i) info->counter++; ...