c / intermediate
Snippet
Atomic Operations with stdatomic.h
The stdatomic.h header (C11) provides types and functions for atomic operations, which are essential for thread-safe programming without the overhead of heavy locks. These operations are guaranteed to be completed in a single step without interruption, preventing data races in concurrent environments.
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#include <stdio.h>#include <stdatomic.h>int main() {_Atomic int counter = 0;// Atomically increments the valueatomic_fetch_add(&counter, 1);// Atomically exchanges valuesint old_val = atomic_exchange(&counter, 10);printf("Old: %d, New: %d\n", old_val, counter);return 0;}
Breakdown
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_Atomic int counter = 0;
Declares an integer that will be accessed using atomic operations.
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atomic_fetch_add(&counter, 1);
Increments the counter safely, returning the previous value.
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atomic_exchange(&counter, 10);
Sets the counter to a new value and returns the old value as an atomic action.