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# os_signpost_interval_begin

Marks the start of a time interval in your code using a signpost.

```
#define os_signpost_interval_begin(log, interval_id, name, ...)
```

## Parameters

`log`

A log object to log the signpost to.

`interval_id`

A signpost identifier used to disambiguate between signposts with the same name.

`name`

The name of the signpost.

`…`

Optional. If specified, provide a format string, followed by the expected number of arguments in the order that they appear in the string.

## Discussion

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

---

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