When Are Semaphores Used?

Semaphores are typically used in one of two ways: To control access to a shared device between tasks. A printer is a good example. You don't want 2 tasks sending to the printer at once, so you create a binary semaphore to control printer access.

When would you use a semaphore example?

General semaphores are used for "counting" tasks such as creating a critical region that allows a specified number of threads to enter. For example, if you want at most four threads to be able to enter a section, you could protect it with a semaphore and initialize that semaphore to four.

Why and when do we use semaphore?

In computer science, a semaphore is a variable or abstract data type used to control access to a common resource by multiple processes and avoid critical section problems in a concurrent system such as a multitasking operating system.