Volatile (computer programming)

In computer programming, a variable is said to be volatile if its value can be read or modified asynchronously by something other than the current thread of execution. The value of a volatile variable may spontaneously change for reasons such as: sharing values with other threads; sharing values with asynchronous signal handlers; accessing hardware devices via memory-mapped I/O (where messages from peripheral devices can be received and sent by reading from and writing to memory).

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