Async handles allow the user to “wakeup” the event loop and get a callback called from another thread.

See also The Handle API functions also apply.

Imports

Types

Async = object loop* {. importc: "loop" .}: ptr Loop ## Pointer to the ``Loop`` where the handle is running on. Readonly. typ* {. importc: "type" .}: HandleType ## The ``HandleType``. Readonly. data* {. importc: "data" .}: pointer ## Space for user-defined arbitrary data. libuv does not use this field.: Async handle type. Source Edit
AsyncCb = proc (handle: Async): Type definition for callback passed to init(). Source Edit

proc init(loop: ptr Loop; handle: ptr Async; cb: AsyncCb): cint {. importc: "uv_async_init", header: "uv.h" .}: Initialize the handle. A nil callback is allowed.
Note: Unlike other handle initialization functions, it immediately starts the handle.
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proc send(handle: ptr Async): cint {. importc: "uv_async_send", header: "uv.h" .}: Wakeup the event loop and call the async handle’s callback.
Note: It’s safe to call this function from any thread. The callback will be called on the loop thread.

Warning libuv will coalesce calls to send(), that is, not every call to it will yield an execution of the callback. For example: if send() is called 5 times in a row before the callback is called, the callback will only be called once. If send() is called again after the callback was called, it will be called again.

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