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# os_signpost(_:dso:log:name:signpostID:_:_:)

Logs a point of interest in your code as a time interval or as an event for debugging performance in Instruments, and includes a detailed message.

```
func os_signpost(_ type: OSSignpostType, dso: UnsafeRawPointer = #dsohandle, log: OSLog, name: StaticString, signpostID: OSSignpostID = .exclusive, _ format: StaticString, _ arguments: any CVarArg...)
```

## Parameters

`type`

The type of signpost to log.

`log`

A log object to log the signpost to.

`name`

The name of the signpost.

`signpostID`

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

`format`

A constant string or format string that produces a human-readable log message.

`arguments`

Additional arguments to substitute into the `format` string parameter. Pass the expected number of arguments in the order that they appear in the string. If `format` is a constant string, don’t include any additional arguments.

## Discussion

---

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