Read-modify-write

Read-modify-write

In computer science, read-modify-write is a class of atomic operations such as test-and-set, fetch-and-add, and compare-and-swap which both read a memory location and write a new value into it simultaneously, either with a completely new value or some function of the previous value.

These operations prevent race conditions in multi-threaded applications. Typically they are used to implement mutexs or semaphores.


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