By default, FLINT will just use one thread. To control the maximum number of threads FLINT uses, one can call the function flint_set_num_threads(n), where $$n$$ is the maximum number of threads to use.
One can also query the current thread limit by calling flint_get_num_threads().
Please refer to $$code_conventions.txt$$ for some preliminary guidance on how to write threaded functions in FLINT.