C++ Handbook

Header Reference: <barrier>

Header Reference: <barrier>

Phase-based synchronization with reusable barriers from <barrier>.

How to use this reference page

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Header Reference: <barrier>

Main facilities

What this header is for

Use <barrier> when a fixed group of participants must repeatedly rendezvous at phase boundaries.

Common patterns

Notes

Minimal example

#include <barrier>

int main() {
    // Use this header when you need explicit coordination between tasks.
    return 0;
}

What to verify before relying on this header

  • How the code will shut down, unblock, or stop safely under cancellation and failure paths.
  • Which state is shared, which synchronization primitive owns that responsibility, and which memory-ordering assumptions are actually required.
  • Whether a higher-level facility such as `std::jthread`, `std::future`, or structured task composition would reduce coordination risk.