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# os_signpost_event_emit

Marks a point of interest in time.

```
#define os_signpost_event_emit(log, event_id, name, ...)
```

## Parameters

`log`

The log that provides the subsystem and category to use. For more information, see [`os_log_create`](/documentation/os/os_log_create).

`event_id`

The event’s identifier.

`name`

The event’s name.

`…`

An optional format string. If you provide the string, you must follow it with any required arguments in the order that they appear in the string.

## Discussion

This function is equivalent to calling [`os_signpost_emit_with_type`](/documentation/os/os_signpost_emit_with_type) with a type of [`OS_SIGNPOST_EVENT`](/documentation/os/os_signpost_type_t/OS_SIGNPOST_EVENT).

---

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