31 lines
1.4 KiB
Plaintext
31 lines
1.4 KiB
Plaintext
:sig
|
|
pid_t task_repeat(String key, f64 interval, std::function<void()> exec_func, u64 timeout = 60*10)
|
|
|
|
:params
|
|
key : string uniquely identifying the task across the whole runtime instance
|
|
interval : repeat interval in seconds
|
|
exec_func : function to execute repeatedly
|
|
timeout : maximum run time in seconds; `0` disables the timeout
|
|
return value : the process ID of the started (or still running) task, or `0` when the task could not be started
|
|
|
|
:see
|
|
>task
|
|
task
|
|
task_pid
|
|
task_kill
|
|
|
|
:content
|
|
Starts a repeating background worker process.
|
|
|
|
`exec_func` runs in a loop, and the worker sleeps for `interval` seconds between executions. `interval` must be greater than zero.
|
|
|
|
If a process with the same `key` is already running anywhere in the runtime instance, `task_repeat()` does not start a second worker and instead returns the PID of the existing one. Coordination is through the same shared task state used by `task()`.
|
|
|
|
`timeout` bounds the lifetime of the repeating worker. The default is ten minutes. Pass `0` only for workers that have another shutdown path. In Wasm, each individual callback invocation remains bounded by the runtime invocation timeout even when the repeating process lifetime is unbounded.
|
|
|
|
:example
|
|
task_repeat("doc-demo-repeat", 60.0, []() { usleep(10000); });
|
|
pid_t pid = task_pid("doc-demo-repeat");
|
|
print(pid > 0 ? "repeating task scheduled" : "not scheduled", "\n");
|
|
if(pid > 0) task_kill(pid);
|