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Sources/Logging OSLog/Docs.docc/index.md

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+# ``LoggingOSLog``
+
+An unified logging backend implementation for SwiftLog.
+
+## Overview
+
+LoggingOSLog is a logging backend implementation for [SwiftLog][swift-log], that
+routes log messages to [OSLog][oslog], the
+[unified logging system][unified-logging] on Apple platforms. On macOS you can
+view the log messages using the Console app or the `log` cli tool.
+
+While SwiftLog is available on all Swift platforms though, the
+unified logging system of OSLog is only available on Apple platforms.
+Use this library to combine both worlds. Use SwiftLog in your codebase and use
+this library as the backend implementation when compiling for an Apple platform,
+i.e. using `#if canImport(Darwin)`.
+
+[unified-logging]: https://developer.apple.com/documentation/os/logging
+[oslog]: https://developer.apple.com/documentation/oslog
+[backend]: https://swiftpackageindex.com/apple/swift-log/1.10.1/documentation/logging
+[swift-log]: https://github.com/apple/swift-log
+
+## Getting started
+
+Use this package if you're writing a cross-platform (for example, Linux and
+macOS) application or library and still want to take full advantage of the
+unified logging system on Apple platforms.
+
+### Adding the Dependency
+
+Add the dependency to your Package.swift:
+
+```swift
+.package(url: "https://github.com/astzweig/swift-log-oslog", from: "1.0.0")
+```
+
+And to your target:
+
+```swift
+.target(
+	name: "YourTarget",
+	dependencies: [
+		.product(name: "LoggingOSLog", package: "swift-log-oslog")
+	]
+)
+```
+
+### Basic Usage
+
+```swift
+// Import the logging API and this backend implementation
+import Logging
+#if canImport(Darwin)
+import LoggingOSLog
+#endif
+
+// Later, in your application initialization code
+func init() {
+	// ...
+	#if canImport(Darwin)
+	LoggingSystem.bootstrap(LoggingOSLog.init)
+	#endif
+
+	// Start creating loggers
+	let loggers: [String: Logger] = [
+		"main": Logger(label: "com.example.yourapp.Main"),
+		"mail": Logger(label: "com.example.yourapp.Mail System"),
+	]
+}
+```
+
+## Relation to the unified logging system
+
+The [unified logging system][unified-logging] uses two parameters to allow for
+better filtering of log messages: [subsystem][subsystem] and
+[category][category]. [SwiftLog][swift-log] has only a label parameter, so this
+library maps a reverse domain style label to the subsystem and category
+parameters of the unified logging system. See
+``/LoggingOSLog/LoggingOSLog/init(label:)`` for more information.
+
+[subsystem]: https://developer.apple.com/documentation/os/generating-log-messages-from-your-code#:~:text=The%20subsystem%20string,for%20each%20subsystem%20string.
+[category]: https://developer.apple.com/documentation/os/generating-log-messages-from-your-code#:~:text=The%20category%20string,for%20these%20strings.
+
+## Topics
+
+### API
+
+- ``LoggingOSLog``