Closes coroutine co, that is, closes all its pending to-be-closed variables and puts the coroutine in a dead state. The given coroutine must be dead or suspended. In case of error closing some variable, returns false plus the error object; otherwise returns true.

coroutine.create (f)

Creates a new coroutine, with body f. f must be a function. Returns this new coroutine, an object with type "thread".

A coroutine is yieldable if it is not the main thread and it is not inside a non-yieldable C function.

coroutine.resume (co [, val1, ···])

Starts or continues the execution of coroutine co. The first time you resume a coroutine, it starts running its body. The values val1, … are passed as the arguments to the body function. If the coroutine has yielded, restarts it; the values val1, … are passed as the results from the yield.

Returns the running coroutine plus a boolean, true when the running coroutine is the main one.

coroutine.status (co)

Returns the status of the coroutine co, as a string: "running", if the coroutine is running (that is, it is the one that called status); "suspended", if the coroutine is suspended in a call to , or if it has not started running yet; "normal" if the coroutine is active but not running (that is, it has resumed another coroutine); and "dead" if the coroutine has finished its body function, or if it has stopped with an error.

coroutine.yield (···)

Suspends the execution of the calling coroutine. Any arguments to yield are passed as extra results to resume.