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# os

Coordinate the scheduling and synchronization of your app’s tasks, and log information to the console to diagnose issues.

## Topics

### Essentials

[Reading UNIX Manual Pages](/documentation/os/reading-unix-manual-pages)

Use the Terminal app to read the documentation for low-level UNIX tools and APIs.

### Logs

[Logging](/documentation/os/logging)

Capture telemetry from your app for debugging and performance analysis using the unified logging system.

### Task Management

[Workgroups](/documentation/os/workgroups)

Schedule one or more threads to run at regular intervals and before specific deadlines.

[Synchronization](/documentation/os/synchronization)

Access low-level synchronization mechanisms to control state across threads.

### Task Management

[Synchronization](/documentation/os/synchronization)

Access low-level synchronization mechanisms to control state across threads.

### Memory

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

Determines the amount of memory available to the current app.

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

A block that takes no arguments and returns no value.

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

A pointer to a function.

[`os_release`](/documentation/os/os_release-c.func)

[`os_retain`](/documentation/os/os_retain-c.func)

### Deprecated

[Deprecated Symbols](/documentation/os/deprecated-symbols)

Review unsupported symbols and their replacements.

### Reference

[os Macros](/documentation/os/os-macros)

[os Data Types](/documentation/os/os-data-types)

### Reference

[os Constants](/documentation/os/os-constants)


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