What does EnterCriticalSection do?

The EnterCriticalSection function waits for ownership of the specified critical section object. The function returns when the calling thread is granted ownership.

What is critical section in C++?

When more than one processes access a same code segment that segment is known as critical section. Critical section contains shared variables or resources which are needed to be synchronized to maintain consistency of data variable.

How do you know if a critical section is initialized?

There is no way to tell if a CRITICAL_SECTION is initialized; you have to keep up with that yourself. In C++, you would wrap it in a class so that it’s initialized when the variable comes into existence. That’s good.

What is a mutex in C++?

A mutex is a lockable object that is designed to signal when critical sections of code need exclusive access, preventing other threads with the same protection from executing concurrently and access the same memory locations.

What is critical section code?

The critical section is a code segment where the shared variables can be accessed. An atomic action is required in a critical section i.e. only one process can execute in its critical section at a time. It acquires the resources needed for execution by the process.

Why mutex is faster than semaphore?

The thread which has acquired mutex can only release Mutex when it exits from critical section. Semaphore value is changed according to wait () and signal () operations. Mutex values can be modified just as locked or unlocked. They are faster than mutex because any other thread/process can unlock binary semaphore.

What happens when you call the entercriticalsection function?

After this function has been called, the critical section object can no longer be used for synchronization. If a thread terminates while it has ownership of a critical section, the state of the critical section is undefined.

When to use critical section in Stack Overflow?

You have ensured that threads aa and bb cannot access the same data at the same time by protecting it with a critical section, but you left it open for the main thread to access it at any time (in the main loop where you print out the array).

How to initialize critical section object in Win32?

// Initialize the critical section one time only. if (!InitializeCriticalSectionAndSpinCount (&CriticalSection, 0x00000400) ) return; // Release resources used by the critical section object.

When to use the leavecriticalsection function in Win32?

When it has finished executing the protected code, the thread uses the LeaveCriticalSection function to relinquish ownership, enabling another thread to become owner and access the protected resource. There is no guarantee about the order in which waiting threads will acquire ownership of the critical section.