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# OSLogMessage

An object that represents a log message.

```
@frozen struct OSLogMessage
```

## Overview> Important:
> You don’t create instances of ``doc://com.apple.os/documentation/os/OSLogMessage`` directly. Instead, the system creates them for you when writing messages to the unified logging system using a ``doc://com.apple.os/documentation/os/Logger``.

## Topics

### Creating a Log Message

### Getting the Message Details

[`bufferSize`](/documentation/os/OSLogMessage/bufferSize)

The byte size of the buffer that the logging system receives.

[`interpolation`](/documentation/os/OSLogMessage/interpolation)

The log message’s string interpolation.

[`maxOSLogArgumentCount`](/documentation/os/maxOSLogArgumentCount)

The maximum number of interpolated expressions that a log message may contain.


---

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