thread

a separate state that can contain and run functions

class thread : public reference { /* ... */ };

sol::thread is a separate runnable part of the Lua VM that can be used to execute work separately from the main thread, such as with coroutines. To take a table or a coroutine and run it specifically on the sol::thread you either pulled out of lua or created, just get that function through the state of the thread

Note

A CPU thread is not always equivalent to a new thread in Lua: std::this_thread::get_id() can be the same for 2 callbacks that have 2 distinct Lua threads. In order to know which thread a callback was called in, hook into sol::this_state from your Lua callback and then construct a sol::thread, passing in the sol::this_state for both the first and last arguments. Then examine the results of the status and is_... calls below.

free function

function: main_thread
main_thread(lua_State* current, lua_State* backup_if_bad_platform = nullptr);

The function sol::main_thread( ... ) retrieves the main thread of the application on Lua 5.2 and above only. It is designed for code that needs to be multithreading-aware (e.g., uses multiple threads and coroutines).

Warning

This code function will be present in Lua 5.1/LuaJIT, but only have proper behavior when given a single argument on Lua 5.2 and beyond. Lua 5.1 does not support retrieving the main thread from its registry, and therefore it is entirely suggested if you are writing cross-platform Lua code that you must store the main thread of your application in some global storage accessible somewhere. Then, pass this item into the sol::main_thread( possibly_thread_state, my_actual_main_state ) and it will select that my_actual_main_state every time. If you are not going to use Lua 5.1 / LuaJIT, you can ignore the last parameter.

members

constructor: thread
thread(stack_reference r);
thread(lua_State* L, int index = -1);
thread(lua_State* L, lua_State* actual_thread);

Takes a thread from the Lua stack at the specified index and allows a person to use all of the abstractions therein. It can also take an actual thread state to make a thread from that as well.

function: view into thread_state()’s state
state_view state() const;

This retrieves the current state of the thread, producing a state_view that can be manipulated like any other. Coroutines pulled from Lua using the thread’s state will be run on that thread specifically.

function: retrieve thread state object
lua_State* thread_state () const;

This function retrieves the lua_State* that represents the thread.

current thread status
thread_status status () const;

Retrieves the thread status that describes the current state of the thread.

main thread status
bool is_main_thread () const;

Checks to see if the thread is the main Lua thread.

function: thread creation
thread create();
static thread create (lua_State* L);

Creates a new thread from the given a lua_State*.