`string, string` or `fail`

                Returns (async version): `uv_getnameinfo_t userdata` or `fail`

==============================================================================
THREADING AND SYNCHRONIZATION UTILITIES *luv-threading-and-synchronization-utilities*

Libuv provides cross-platform implementations for multiple threading and
synchronization primitives. The API largely follows the pthreads API.

uv.new_thread([{options}, ] {entry}, {...})                    *uv.new_thread()*

                Parameters:
                - `options`: `table` or `nil`
                  - `stack_size`: `integer` or `nil`
                - `entry`: `function` or `string`
                - `...`: `threadargs` passed to `entry`

                Creates and initializes a `luv_thread_t` (not `uv_thread_t`).
                Returns the Lua userdata wrapping it and asynchronously
                executes `entry`, which can be either a Lua function or a
                string containing Lua code or bytecode dumped from a function.
                Additional arguments `...` are passed to the `entry` function
                and an optional `options` table may be provided. Currently
                accepted `option` fields are `stack_size`.

                Returns: `luv_thread_t userdata` or `fail`

                Note: unsafe, please make sure that the thread's end of life
                is before Lua state is closed.

uv.thread_equal({thread}, {other_thread})                    *uv.thread_equal()*

                > method form `thread:equal(other_thread)`

                Parameters:
                - `thread`: `luv_thread_t userdata`
                - `other_thread`: `luv_thread_t userdata`

                Returns a boolean indicating whether two threads are the same.
                This function is equivalent to the `__eq` metamethod.

                Returns: `boolean`
                                                     *uv.thread_setaffinity()*
uv.thread_setaffinity({thread}, {affinity} [, {get_old_affinity}])

                > method form `thread:setaffinity(affinity, [get_old_affinity])`

                Parameters:
                - `thread`: `luv_thread_t userdata`
                - `affinity`: `table`
                  - `[1, 2, 3, ..., n]` : `boolean`
                - `get_old_affinity`: `boolean`

                Sets the specified thread's affinity setting.

                `affinity` must be a table where each of the keys are a CPU
                number and the values are booleans that represent whether the
                `thread` should be eligible to run on that CPU. If the length
                of the `affinity` table is not greater than or equal to
                |uv.cpumask_size()|, any CPU numbers missing from the table
                will have their affinity set to `false`. If setting the
                affinity of more than |uv.cpumask_size()| CPUs is desired,
                `affinity` must be an array-like table with no gaps, since
                `#affinity` will be used as the `cpumask_size` if it is
                greater than |uv.cpumask_size()|.

                If `get_old_affinity` is `true`, the previous affinity
                settings for the `thread` will be returned. Otherwise, `true`
                is returned after a successful call.

                Note: Thread affinity setting is not atomic on Windows.
                Unsupported on macOS.

                Returns: `table` or `boolean` or `fail`
                - `[1, 2, 3, ..., n]` : `boolean`


uv.thread_getaffinity({thread} [, {mask_size}])        *uv.thread_getaffinity()*

                > method form `thread:getaffinity([mask_size])`

                Parameters:
                - `thread`: `luv_thread_t userdata`
                - `mask_size`: `integer`

                Gets the specified thread's affinity setting.

                If `mask_size` is provided, it must be greater than or equal
                to `uv.cpumask_size()`.