# os_log_t A log object that you pass to logging functions to send messages to that log. ## Topics ### Getting the Standard Log Objects [`#define OS_LOG_DEFAULT`](/documentation/os/OS_LOG_DEFAULT) The shared default log. [`#define OS_LOG_DISABLED`](/documentation/os/OS_LOG_DISABLED) The shared disabled log. ### Creating a Log Object [`extern os_log_tos_log_create(const char *subsystem, const char *category);`](/documentation/os/os_log_create) Creates a custom log object. ### Getting Log Configuration [`#define os_log_info_enabled(log)`](/documentation/os/os_log_info_enabled) Returns a Boolean value that indicates whether info-level logging is in an enabled state for a specified log object. [`#define os_log_debug_enabled(log)`](/documentation/os/os_log_debug_enabled) Returns a Boolean value that indicates whether debug-level logging is in an enabled state for a specified log object. [`func isEnabled(type: OSLogType) -> Bool`](/documentation/os/OSLog/isEnabled(type:)) Returns a Boolean value that indicates whether the log can write messages with the specified log type. [`extern bool os_signpost_enabled(os_log_t log);`](/documentation/os/os_signpost_enabled) Returns a Boolean value that indicates whether signposts are in an enabled state for the specified log. ### Data Types [`typedef NSObject * os_log_t;`](/documentation/os/os_log_t) A log object that you pass to logging functions to send messages to that log. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)