Provides POSIX semaphores (counting semaphores).
Standard POSIX mutexes and condition variables.
No priority inversion but specific inheritance mechanism called priority tracking (see driver section).
Simple inheritance, immediate ceiling, etc.
Priority inheritance is implemented via binary semaphores. When a high priority task wants a resource held by a lower priority task, the lower priority task's priority is boosted to that of the higher priority task until the resource is released. This mechanism is used in the LynxOS® kernel and is available to applications and drivers.
The default protocol attribute of pthread_mutextattrr_t is PTHREAD_PRIO_INHERIT so the prioceiling attribute is irrelevant.
yes
Synchronous or/and Asynchronous, prioritized messages, etc.
yes.
Them mmap() support for regular files and shared memory.
LynxOS provides a thread safe version of the standard 'C' library with extensions for higher performance.