pWaitSemaphores

pWaitSemaphores are a fundamental synchronization primitive used in concurrent programming. They are a type of semaphore, which is a signaling mechanism that controls access to a shared resource by multiple processes or threads. A pWaitSemaphore, specifically, is designed to facilitate a "wait" or "decrement" operation. When a process or thread attempts to acquire a pWaitSemaphore, it first checks its value. If the value is greater than zero, the value is decremented, and the process or thread continues execution. If the value is zero, the process or thread is blocked and must wait until another process or thread signals the semaphore, increasing its value.

The primary purpose of pWaitSemaphores is to prevent race conditions and ensure orderly access to resources that can only be used by a limited number of entities at a time. For example, a pWaitSemaphores could be initialized with the number of available connections in a connection pool. Each thread wanting a connection would attempt to acquire the semaphore. If successful, it uses a connection. When a thread finishes with a connection, it signals the semaphore, making it available for another waiting thread. This mechanism ensures that no more than the allowed number of connections are in use simultaneously. They are a key tool for managing shared resources and coordinating the execution of concurrent tasks.