Final answer:
A synchronous call is implemented in the Intel TBB library using mechanisms such as explicit task creation and synchronization using the tbb::task class, as well as the ability to invoke multiple tasks in parallel and wait for their completion using the tbb::parallel_invoke function.
Step-by-step explanation:
In the Intel TBB library, a synchronous call is implemented using various mechanisms provided by the library. One such mechanism is the tbb::task class, which allows for explicit task creation and synchronization. Synchronous calls can be implemented by creating task objects and using the tbb::task::wait_for_all function to wait for all tasks to complete.
Another mechanism provided by the TBB library is the tbb::parallel_invoke function, which allows invoking multiple callable objects in parallel and waiting for their completion synchronously.
In summary, Intel TBB provides mechanisms such as explicit task creation and synchronization using the tbb::task class, as well as the ability to invoke multiple tasks in parallel and wait for their completion using the tbb::parallel_invoke function.