wasm-micro-runtime/doc/embed_wamr_spawn_api.md

39 lines
1.5 KiB
Markdown
Raw Normal View History

# Thread related embedder API
This document explains `wasm_runtime_spawn_exec_env` and
`wasm_runtime_spawn_thread`.
[Here](../samples/spawn-thread) is a sample to show how to use these APIs.
* spawn exec_env
`spawn exec_env` API creates a new `exec_env` based on the original `exec_env`. You can use it in other threads. It's up to the embedder how to manage host threads to run the new `exec_env`.
```C
new_exec_env = wasm_runtime_spawn_exec_env(exec_env);
/* Then you can use new_exec_env in your new thread */
module_inst = wasm_runtime_get_module_inst(new_exec_env);
func_inst = wasm_runtime_lookup_function(module_inst, ...);
wasm_runtime_call_wasm(new_exec_env, func_inst, ...);
/* you need to use this API to manually destroy the spawned exec_env */
wasm_runtime_destroy_spawned_exec_env(new_exec_env);
```
* spawn thread
Alternatively, you can use `spawn thread` API to avoid managing the extra exec_env and the corresponding host thread manually:
```C
wasm_thread_t wasm_tid;
void *wamr_thread_cb(wasm_exec_env_t exec_env, void *arg)
{
module_inst = wasm_runtime_get_module_inst(exec_env);
func_inst = wasm_runtime_lookup_function(module_inst, ...);
wasm_runtime_call_wasm(exec_env, func_inst, ...);
}
wasm_runtime_spawn_thread(exec_env, &wasm_tid, wamr_thread_cb, NULL);
/* Use wasm_runtime_join_thread to join the spawned thread */
wasm_runtime_join_thread(wasm_tid, NULL);
```