What tasks does the sync package in Go solve?

The sync package in Go provides synchronization primitives for managing concurrent access to resources and coordinating goroutines.

The main tasks solved by the sync package:

• Mutexes (Mutex) — for protecting critical sections and preventing simultaneous access to shared data.
• RWMutex — a mutex with separate read and write locks, allowing multiple goroutines to read data simultaneously but blocking writes.
• WaitGroup — for waiting for a group of goroutines to finish.
• Once — for executing initialization only once.

Example of using Mutex:

var mu sync.Mutex
var counter int

func increment() {
    mu.Lock()
    defer mu.Unlock()
    counter++
}

Thus, the sync package helps to work safely with concurrency and avoid data races.