---
title: os_signpost_interval_begin
framework: os
role: symbol
role_heading: Macro
path: os/os_signpost_interval_begin
---

# os_signpost_interval_begin

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

## Declaration

```occ
#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

Discussion Calling this function is equivalent to calling os_signpost_emit_with_type with a type of OS_SIGNPOST_INTERVAL_BEGIN.

## See Also

### Measure Events

- [Recording Performance Data](os/recording-performance-data.md)
- [Legacy Signpost Symbols](os/legacy-signpost-symbols.md)
- [os_signpost_emit_with_type](os/os_signpost_emit_with_type.md)
- [OSSignpostType](os/ossignposttype.md)
- [os_signpost_interval_end](os/os_signpost_interval_end.md)
- [os_signpost_event_emit](os/os_signpost_event_emit.md)
- [os_signpost_id_t](os/os_signpost_id_t.md)