Definition: Critical resources are resources that can only be accessed by one process or thread at a time. For example, printers, shared files, variables, etc.
Characteristics: Access to critical resources needs to be exclusive, which means that at a certain point in time, only one process or thread can use the resource, and other processes must wait.
Critical Section
Definition: The critical section refers to the code in the program that accesses the critical resource. The code that enters the critical section needs to be strictly controlled to prevent multiple processes or threads from entering at the same time, thereby avoiding race conditions and data inconsistency.
Control: Synchronization mechanisms such as mutexes, semaphores, or other locking mechanisms are usually used to ensure exclusive access to the critical section.