1# Threading 2 3The Open Screen Library is **single-threaded**; all of its code is intended to be 4run on a single sequence, with a few exceptions noted below. 5 6A library client **must** invoke all library APIs on the same sequence that is 7used to run tasks on the client's 8[TaskRunner implementation](https://chromium.googlesource.com/openscreen/+/refs/heads/master/platform/api/task_runner.h). 9 10## Exceptions 11 12* The [trace logging](trace_logging.md) framework is thread-safe. 13* The TaskRunner itself is thread-safe. 14* The [POSIX platform implementation](https://chromium.googlesource.com/openscreen/+/refs/heads/master/platform/impl/) 15 starts a network thread, and handles interactions between that thread and the 16 TaskRunner internally. 17 18 19 20 21 22