/usr/share/man/man3/ is in libdispatch-dev 0~svn197-3.1ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/man/man3/dispatch_source_create.3.gz
/usr/share/man/man3/dispatch_group_create.3.gz
/usr/share/man/man3/dispatch_queue_create.3.gz
/usr/share/man/man3/dispatch_object.3.gz
/usr/share/man/man3/dispatch_time.3.gz
/usr/share/man/man3/dispatch_async.3.gz
/usr/share/man/man3/dispatch_after.3.gz
/usr/share/man/man3/dispatch_apply.3.gz
/usr/share/man/man3/dispatch_once.3.gz
/usr/share/man/man3/dispatch_api.3.gz
/usr/share/man/man3/dispatch_semaphore_create.3.gz
/usr/share/man/man3/dispatch_benchmark.3.gz
/usr/share/man/man3/dispatch.3.gz
/usr/share/man/man3/dispatch_group_notify.3.gz
/usr/share/man/man3/dispatch_source_testcancel.3.gz
/usr/share/man/man3/dispatch_group_enter.3.gz
/usr/share/man/man3/dispatch_group_async.3.gz
/usr/share/man/man3/dispatch_sync_f.3.gz
/usr/share/man/man3/dispatch_source_set_event_handler_f.3.gz
/usr/share/man/man3/dispatch_get_main_queue.3.gz
/usr/share/man/man3/dispatch_source_set_timer.3.gz
/usr/share/man/man3/dispatch_source_get_data.3.gz
/usr/share/man/man3/dispatch_source_merge_data.3.gz
/usr/share/man/man3/dispatch_main.3.gz
/usr/share/man/man3/dispatch_group_async_f.3.gz
/usr/share/man/man3/dispatch_apply_f.3.gz
/usr/share/man/man3/dispatch_source_cancel.3.gz
/usr/share/man/man3/dispatch_release.3.gz
/usr/share/man/man3/dispatch_once_f.3.gz
/usr/share/man/man3/dispatch_benchmark_f.3.gz
/usr/share/man/man3/dispatch_source_get_mask.3.gz
/usr/share/man/man3/dispatch_set_target_queue.3.gz
/usr/share/man/man3/dispatch_group_notify_f.3.gz
/usr/share/man/man3/dispatch_group_leave.3.gz
/usr/share/man/man3/dispatch_resume.3.gz
/usr/share/man/man3/dispatch_sync.3.gz
/usr/share/man/man3/dispatch_async_f.3.gz
/usr/share/man/man3/dispatch_source_set_cancel_handler_f.3.gz
/usr/share/man/man3/dispatch_semaphore_signal.3.gz
/usr/share/man/man3/dispatch_set_finalizer_f.3.gz
/usr/share/man/man3/dispatch_after_f.3.gz
/usr/share/man/man3/dispatch_semaphore_wait.3.gz
/usr/share/man/man3/dispatch_source_set_event_handler.3.gz
/usr/share/man/man3/dispatch_get_global_queue.3.gz
/usr/share/man/man3/dispatch_source_set_cancel_handler.3.gz
/usr/share/man/man3/dispatch_retain.3.gz
/usr/share/man/man3/dispatch_queue_get_label.3.gz
/usr/share/man/man3/dispatch_suspend.3.gz
/usr/share/man/man3/dispatch_source_get_handle.3.gz
/usr/share/man/man3/dispatch_set_context.3.gz
/usr/share/man/man3/dispatch_group_wait.3.gz
/usr/share/man/man3/dispatch_walltime.3.gz
/usr/share/man/man3/dispatch_get_current_queue.3.gz
/usr/share/man/man3/dispatch_get_context.3.gz